Merge ~ubuntu-docker-images/ubuntu-docker-images/+git/redis:readme into ~ubuntu-docker-images/ubuntu-docker-images/+git/redis:edge

[Sergio Durigan Junior]

Improve on the existing README file; add HACKING and examples. As per requested by LP #1904004.

[Richard Harding (rharding)]

Awesome, ty. A couple of clean up please, but with those this looks like a great start.

review: Approve

[Sergio Durigan Junior (sergiodj)]

Thanks for the review, Rick! I've addressed your comments, and will push the changes now.

diff --git a/HACKING.md b/HACKING.md
 new file mode 100644
index 0000000..4de80f4
--- /dev/null
+++ b/HACKING.md
@@ -0,0 +1,19 @@
+# Contributing
+
+In order to contribute to the redis OCI image, do the following:
+
+* Create a new branch.
+
+* Make your changes. Keep your commits logically separated. If it is
+  fixing a bug do not forget to mention it in the commit message.
+
+* Build a new image with your changes. You can use the following command:
+
+```
+$ docker build -t squeakywheel/redis:test .
+```
+
+* Test the new image. Run it in some way that exercise your changes,
+  you can also check th README.md file.
+
+* If everything goes well submit a merge proposal.
diff --git a/README.md b/README.md
index 4011330..77cd3bc 100644
--- a/README.md
+++ b/README.md
@@ -1,21 +1,42 @@
 # Ubuntu redis OCI image
 
-This is the OCI image for redis.
+This is the OCI image for redis.  In Ubuntu, redis is available as a
+`.deb.` package.  For this reason, this image was built by installing
+the redis Ubuntu Focal package inside a docker container.
+
+## Versions supported
+
+* `edge` = `5.0.7-2`
+
+## Architectures supported
+
+* amd64
+
+* arm64
+
+* ppc64el
+
+* s390x
 
 ## How to use it
 
-`$ docker run --name redis -e ALLOW_EMPTY_PASSWORD=yes <TODONAMEHERE>/redis:edge`
+To obtain this image, run:
 
-Bear in mind that the use of `ALLOW_EMPTY_PASSWORD=yes` is not
-recommended in production environments.
+```
+$ docker pull squeakywheel/redis:edge
+```
 
-## Differences between our image and upstream's
+You will be able to launch `redis-server` by doing:
 
-Upstream's redis image does not enforce the use of a password when
-connecting to `redis-server`, whereas our image does.  For this
-reason, you have to explicitly provide the password via an environment
-variable (see below), or disable it via the
-`ALLOW_EMPTY_PASSWORD=yes`, as mentioned above.
+```
+$ docker run --name redis -e ALLOW_EMPTY_PASSWORD=yes squeakywheel/redis:edge
+```
+
+Bear in mind that the use of `ALLOW_EMPTY_PASSWORD=yes` is not
+recommended in production environments.  For production environments,
+it is recommended that you specify the `REDIS_PASSWORD` environment
+variable, or instruct the entrypoint script to create a random
+password for you by specifying `REDIS_RANDOM_PASSWORD=1`.
 
 ## Environment variables
 
@@ -42,3 +63,61 @@ the behaviour of `redis-server`.
 - `REDIS_EXTRA_FLAGS`: If you would like to specify any extra flags to
   be passed to `redis-server` when initializing it, use this
   environment variable to do so.
+
+## Specifying your own configuration file
+
+You can specify your own `redis.conf` file by mounting it:
+
+```
+$ docker run -v /myredis/redis.conf:/etc/redis/redis.conf -e ALLOW_EMPTY_PASSWORD=yes --name redis squeakywheel/redis:edge
+```
+
+## Connecting to the redis-server via redis-cli
+
+If you want, you can launch another container with the `redis-cli`
+program, and connect to the `redis-server` that is running in the
+first container.
+
+For example, suppose that you already have a docker network named
+`redis-network` configured, and you launch `redis-server` like this:
+
+```
+$ docker run --network redis-network --name redis-container -e REDIS_PASSWORD=mypassword -d squeakywheel/redis:edge
+```
+
+You can now launch `redis-cli` by doing:
+
+```
+$ docker run --network redis-network --rm squeakywheel/redis:edge redis-cli -h redis-container
+redis:6379> AUTH mypassword
+OK
+redis:6379> PING
+PONG
+redis:6379>
+```
+
+## Differences between our image and upstream's
+
+Upstream's redis image does not enforce the use of a password when
+connecting to `redis-server`, whereas our image does.  For this
+reason, you have to explicitly provide the password via an environment
+variable (see below), or disable it via the
+`ALLOW_EMPTY_PASSWORD=yes`, as mentioned above.
+
+## Bugs and Features request
+
+If you find a bug in our image or want to request a specific feature
+file a bug here:
+
+https://bugs.launchpad.net/ubuntu-server-oci/+filebug
+
+In the title of the bug add `redis: <reason>`.
+
+Make sure to include:
+
+* The tag of the image you are using
+
+* Reproduction steps for the deployment
+
+* If it is a feature request, please provide as much detail as
+  possible
diff --git a/examples/README.md b/examples/README.md
 new file mode 100644
index 0000000..09e3cd1
--- /dev/null
+++ b/examples/README.md
@@ -0,0 +1,74 @@
+# Running the examples
+
+## docker-compose
+
+Install `docker-compose` from the Ubuntu archive:
+
+```
+$ sudo apt install -y docker-compose
+```
+
+Call `docker-compose` from the examples directory:
+
+```
+$ docker-compose up -d
+```
+
+You can now access the redis server on port 6379, using `redis-cli`:
+
+```
+$ redis-cli -h 127.0.0.1
+127.0.0.1:6379> auth mypassword
+OK
+127.0.0.1:6379> ping
+PONG
+127.0.0.1:6379> 
+```
+
+Notice that the default password set in the `docker-compose` file is
+`mypassword`.
+
+To stop `docker-compose`, run:
+
+```
+$ docker-compose down
+```
+
+# Microk8s
+
+Install microk8s from snap:
+
+```
+$ snap install microk8s
+```
+
+With microk8s running, enable the `dns` and `storage` add-ons:
+
+```
+$ microk8s enable dns storage
+```
+
+Create a configmap for the configuration files:
+
+```
+$ microk8s kubectl create configmap redis-config \
+		--from-file=redis=config/redis.conf \
+```
+
+Apply the `microk8s-deployments.yml`:
+
+```
+$ microk8s kubectl apply -f microk8s-deployments.yml
+```
+
+You will now be able to connect to the redis server using port 30073
+on `localhost`:
+
+```
+$ redis-cli -h 127.0.0.1 -p 30073
+127.0.0.1:30073> auth mypassword
+OK
+127.0.0.1:30073> ping
+PONG
+127.0.0.1:30073> 
+```
diff --git a/examples/config/redis.conf b/examples/config/redis.conf
 new file mode 100644
index 0000000..d01b31e
--- /dev/null
+++ b/examples/config/redis.conf
@@ -0,0 +1,1373 @@
+# Redis configuration file example.
+#
+# Note that in order to read the configuration file, Redis must be
+# started with the file path as first argument:
+#
+# ./redis-server /path/to/redis.conf
+
+# Note on units: when memory size is needed, it is possible to specify
+# it in the usual form of 1k 5GB 4M and so forth:
+#
+# 1k => 1000 bytes
+# 1kb => 1024 bytes
+# 1m => 1000000 bytes
+# 1mb => 1024*1024 bytes
+# 1g => 1000000000 bytes
+# 1gb => 1024*1024*1024 bytes
+#
+# units are case insensitive so 1GB 1Gb 1gB are all the same.
+
+################################## INCLUDES ###################################
+
+# Include one or more other config files here.  This is useful if you
+# have a standard template that goes to all Redis servers but also need
+# to customize a few per-server settings.  Include files can include
+# other files, so use this wisely.
+#
+# Notice option "include" won't be rewritten by command "CONFIG REWRITE"
+# from admin or Redis Sentinel. Since Redis always uses the last processed
+# line as value of a configuration directive, you'd better put includes
+# at the beginning of this file to avoid overwriting config change at runtime.
+#
+# If instead you are interested in using includes to override configuration
+# options, it is better to use include as the last line.
+#
+# include /path/to/local.conf
+# include /path/to/other.conf
+
+################################## MODULES #####################################
+
+# Load modules at startup. If the server is not able to load modules
+# it will abort. It is possible to use multiple loadmodule directives.
+#
+# loadmodule /path/to/my_module.so
+# loadmodule /path/to/other_module.so
+
+################################## NETWORK #####################################
+
+# By default, if no "bind" configuration directive is specified, Redis listens
+# for connections from all the network interfaces available on the server.
+# It is possible to listen to just one or multiple selected interfaces using
+# the "bind" configuration directive, followed by one or more IP addresses.
+#
+# Examples:
+#
+# bind 192.168.1.100 10.0.0.1
+# bind 127.0.0.1 ::1
+#
+# ~~~ WARNING ~~~ If the computer running Redis is directly exposed to the
+# internet, binding to all the interfaces is dangerous and will expose the
+# instance to everybody on the internet. So by default we uncomment the
+# following bind directive, that will force Redis to listen only into
+# the IPv4 loopback interface address (this means Redis will be able to
+# accept connections only from clients running into the same computer it
+# is running).
+#
+# IF YOU ARE SURE YOU WANT YOUR INSTANCE TO LISTEN TO ALL THE INTERFACES
+# JUST COMMENT THE FOLLOWING LINE.
+# ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+#bind 127.0.0.1 ::1
+bind 0.0.0.0
+
+# Protected mode is a layer of security protection, in order to avoid that
+# Redis instances left open on the internet are accessed and exploited.
+#
+# When protected mode is on and if:
+#
+# 1) The server is not binding explicitly to a set of addresses using the
+#    "bind" directive.
+# 2) No password is configured.
+#
+# The server only accepts connections from clients connecting from the
+# IPv4 and IPv6 loopback addresses 127.0.0.1 and ::1, and from Unix domain
+# sockets.
+#
+# By default protected mode is enabled. You should disable it only if
+# you are sure you want clients from other hosts to connect to Redis
+# even if no authentication is configured, nor a specific set of interfaces
+# are explicitly listed using the "bind" directive.
+protected-mode yes
+
+# Accept connections on the specified port, default is 6379 (IANA #815344).
+# If port 0 is specified Redis will not listen on a TCP socket.
+port 6379
+
+# TCP listen() backlog.
+#
+# In high requests-per-second environments you need an high backlog in order
+# to avoid slow clients connections issues. Note that the Linux kernel
+# will silently truncate it to the value of /proc/sys/net/core/somaxconn so
+# make sure to raise both the value of somaxconn and tcp_max_syn_backlog
+# in order to get the desired effect.
+tcp-backlog 511
+
+# Unix socket.
+#
+# Specify the path for the Unix socket that will be used to listen for
+# incoming connections. There is no default, so Redis will not listen
+# on a unix socket when not specified.
+#
+# unixsocket /var/run/redis/redis-server.sock
+# unixsocketperm 700
+
+# Close the connection after a client is idle for N seconds (0 to disable)
+timeout 0
+
+# TCP keepalive.
+#
+# If non-zero, use SO_KEEPALIVE to send TCP ACKs to clients in absence
+# of communication. This is useful for two reasons:
+#
+# 1) Detect dead peers.
+# 2) Take the connection alive from the point of view of network
+#    equipment in the middle.
+#
+# On Linux, the specified value (in seconds) is the period used to send ACKs.
+# Note that to close the connection the double of the time is needed.
+# On other kernels the period depends on the kernel configuration.
+#
+# A reasonable value for this option is 300 seconds, which is the new
+# Redis default starting with Redis 3.2.1.
+tcp-keepalive 300
+
+################################# GENERAL #####################################
+
+# By default Redis does not run as a daemon. Use 'yes' if you need it.
+# Note that Redis will write a pid file in /var/run/redis.pid when daemonized.
+daemonize yes
+
+# If you run Redis from upstart or systemd, Redis can interact with your
+# supervision tree. Options:
+#   supervised no      - no supervision interaction
+#   supervised upstart - signal upstart by putting Redis into SIGSTOP mode
+#   supervised systemd - signal systemd by writing READY=1 to $NOTIFY_SOCKET
+#   supervised auto    - detect upstart or systemd method based on
+#                        UPSTART_JOB or NOTIFY_SOCKET environment variables
+# Note: these supervision methods only signal "process is ready."
+#       They do not enable continuous liveness pings back to your supervisor.
+supervised no
+
+# If a pid file is specified, Redis writes it where specified at startup
+# and removes it at exit.
+#
+# When the server runs non daemonized, no pid file is created if none is
+# specified in the configuration. When the server is daemonized, the pid file
+# is used even if not specified, defaulting to "/var/run/redis.pid".
+#
+# Creating a pid file is best effort: if Redis is not able to create it
+# nothing bad happens, the server will start and run normally.
+pidfile /var/run/redis/redis-server.pid
+
+# Specify the server verbosity level.
+# This can be one of:
+# debug (a lot of information, useful for development/testing)
+# verbose (many rarely useful info, but not a mess like the debug level)
+# notice (moderately verbose, what you want in production probably)
+# warning (only very important / critical messages are logged)
+loglevel notice
+
+# Specify the log file name. Also the empty string can be used to force
+# Redis to log on the standard output. Note that if you use standard
+# output for logging but daemonize, logs will be sent to /dev/null
+logfile /var/log/redis/redis-server.log
+
+# To enable logging to the system logger, just set 'syslog-enabled' to yes,
+# and optionally update the other syslog parameters to suit your needs.
+# syslog-enabled no
+
+# Specify the syslog identity.
+# syslog-ident redis
+
+# Specify the syslog facility. Must be USER or between LOCAL0-LOCAL7.
+# syslog-facility local0
+
+# Set the number of databases. The default database is DB 0, you can select
+# a different one on a per-connection basis using SELECT <dbid> where
+# dbid is a number between 0 and 'databases'-1
+databases 16
+
+# By default Redis shows an ASCII art logo only when started to log to the
+# standard output and if the standard output is a TTY. Basically this means
+# that normally a logo is displayed only in interactive sessions.
+#
+# However it is possible to force the pre-4.0 behavior and always show a
+# ASCII art logo in startup logs by setting the following option to yes.
+always-show-logo yes
+
+################################ SNAPSHOTTING  ################################
+#
+# Save the DB on disk:
+#
+#   save <seconds> <changes>
+#
+#   Will save the DB if both the given number of seconds and the given
+#   number of write operations against the DB occurred.
+#
+#   In the example below the behaviour will be to save:
+#   after 900 sec (15 min) if at least 1 key changed
+#   after 300 sec (5 min) if at least 10 keys changed
+#   after 60 sec if at least 10000 keys changed
+#
+#   Note: you can disable saving completely by commenting out all "save" lines.
+#
+#   It is also possible to remove all the previously configured save
+#   points by adding a save directive with a single empty string argument
+#   like in the following example:
+#
+#   save ""
+
+save 900 1
+save 300 10
+save 60 10000
+
+# By default Redis will stop accepting writes if RDB snapshots are enabled
+# (at least one save point) and the latest background save failed.
+# This will make the user aware (in a hard way) that data is not persisting
+# on disk properly, otherwise chances are that no one will notice and some
+# disaster will happen.
+#
+# If the background saving process will start working again Redis will
+# automatically allow writes again.
+#
+# However if you have setup your proper monitoring of the Redis server
+# and persistence, you may want to disable this feature so that Redis will
+# continue to work as usual even if there are problems with disk,
+# permissions, and so forth.
+stop-writes-on-bgsave-error yes
+
+# Compress string objects using LZF when dump .rdb databases?
+# For default that's set to 'yes' as it's almost always a win.
+# If you want to save some CPU in the saving child set it to 'no' but
+# the dataset will likely be bigger if you have compressible values or keys.
+rdbcompression yes
+
+# Since version 5 of RDB a CRC64 checksum is placed at the end of the file.
+# This makes the format more resistant to corruption but there is a performance
+# hit to pay (around 10%) when saving and loading RDB files, so you can disable it
+# for maximum performances.
+#
+# RDB files created with checksum disabled have a checksum of zero that will
+# tell the loading code to skip the check.
+rdbchecksum yes
+
+# The filename where to dump the DB
+dbfilename dump.rdb
+
+# The working directory.
+#
+# The DB will be written inside this directory, with the filename specified
+# above using the 'dbfilename' configuration directive.
+#
+# The Append Only File will also be created inside this directory.
+#
+# Note that you must specify a directory here, not a file name.
+dir /var/lib/redis
+
+################################# REPLICATION #################################
+
+# Master-Replica replication. Use replicaof to make a Redis instance a copy of
+# another Redis server. A few things to understand ASAP about Redis replication.
+#
+#   +------------------+      +---------------+
+#   |      Master      | ---> |    Replica    |
+#   | (receive writes) |      |  (exact copy) |
+#   +------------------+      +---------------+
+#
+# 1) Redis replication is asynchronous, but you can configure a master to
+#    stop accepting writes if it appears to be not connected with at least
+#    a given number of replicas.
+# 2) Redis replicas are able to perform a partial resynchronization with the
+#    master if the replication link is lost for a relatively small amount of
+#    time. You may want to configure the replication backlog size (see the next
+#    sections of this file) with a sensible value depending on your needs.
+# 3) Replication is automatic and does not need user intervention. After a
+#    network partition replicas automatically try to reconnect to masters
+#    and resynchronize with them.
+#
+# replicaof <masterip> <masterport>
+
+# If the master is password protected (using the "requirepass" configuration
+# directive below) it is possible to tell the replica to authenticate before
+# starting the replication synchronization process, otherwise the master will
+# refuse the replica request.
+#
+# masterauth <master-password>
+
+# When a replica loses its connection with the master, or when the replication
+# is still in progress, the replica can act in two different ways:
+#
+# 1) if replica-serve-stale-data is set to 'yes' (the default) the replica will
+#    still reply to client requests, possibly with out of date data, or the
+#    data set may just be empty if this is the first synchronization.
+#
+# 2) if replica-serve-stale-data is set to 'no' the replica will reply with
+#    an error "SYNC with master in progress" to all the kind of commands
+#    but to INFO, replicaOF, AUTH, PING, SHUTDOWN, REPLCONF, ROLE, CONFIG,
+#    SUBSCRIBE, UNSUBSCRIBE, PSUBSCRIBE, PUNSUBSCRIBE, PUBLISH, PUBSUB,
+#    COMMAND, POST, HOST: and LATENCY.
+#
+replica-serve-stale-data yes
+
+# You can configure a replica instance to accept writes or not. Writing against
+# a replica instance may be useful to store some ephemeral data (because data
+# written on a replica will be easily deleted after resync with the master) but
+# may also cause problems if clients are writing to it because of a
+# misconfiguration.
+#
+# Since Redis 2.6 by default replicas are read-only.
+#
+# Note: read only replicas are not designed to be exposed to untrusted clients
+# on the internet. It's just a protection layer against misuse of the instance.
+# Still a read only replica exports by default all the administrative commands
+# such as CONFIG, DEBUG, and so forth. To a limited extent you can improve
+# security of read only replicas using 'rename-command' to shadow all the
+# administrative / dangerous commands.
+replica-read-only yes
+
+# Replication SYNC strategy: disk or socket.
+#
+# -------------------------------------------------------
+# WARNING: DISKLESS REPLICATION IS EXPERIMENTAL CURRENTLY
+# -------------------------------------------------------
+#
+# New replicas and reconnecting replicas that are not able to continue the replication
+# process just receiving differences, need to do what is called a "full
+# synchronization". An RDB file is transmitted from the master to the replicas.
+# The transmission can happen in two different ways:
+#
+# 1) Disk-backed: The Redis master creates a new process that writes the RDB
+#                 file on disk. Later the file is transferred by the parent
+#                 process to the replicas incrementally.
+# 2) Diskless: The Redis master creates a new process that directly writes the
+#              RDB file to replica sockets, without touching the disk at all.
+#
+# With disk-backed replication, while the RDB file is generated, more replicas
+# can be queued and served with the RDB file as soon as the current child producing
+# the RDB file finishes its work. With diskless replication instead once
+# the transfer starts, new replicas arriving will be queued and a new transfer
+# will start when the current one terminates.
+#
+# When diskless replication is used, the master waits a configurable amount of
+# time (in seconds) before starting the transfer in the hope that multiple replicas
+# will arrive and the transfer can be parallelized.
+#
+# With slow disks and fast (large bandwidth) networks, diskless replication
+# works better.
+repl-diskless-sync no
+
+# When diskless replication is enabled, it is possible to configure the delay
+# the server waits in order to spawn the child that transfers the RDB via socket
+# to the replicas.
+#
+# This is important since once the transfer starts, it is not possible to serve
+# new replicas arriving, that will be queued for the next RDB transfer, so the server
+# waits a delay in order to let more replicas arrive.
+#
+# The delay is specified in seconds, and by default is 5 seconds. To disable
+# it entirely just set it to 0 seconds and the transfer will start ASAP.
+repl-diskless-sync-delay 5
+
+# Replicas send PINGs to server in a predefined interval. It's possible to change
+# this interval with the repl_ping_replica_period option. The default value is 10
+# seconds.
+#
+# repl-ping-replica-period 10
+
+# The following option sets the replication timeout for:
+#
+# 1) Bulk transfer I/O during SYNC, from the point of view of replica.
+# 2) Master timeout from the point of view of replicas (data, pings).
+# 3) Replica timeout from the point of view of masters (REPLCONF ACK pings).
+#
+# It is important to make sure that this value is greater than the value
+# specified for repl-ping-replica-period otherwise a timeout will be detected
+# every time there is low traffic between the master and the replica.
+#
+# repl-timeout 60
+
+# Disable TCP_NODELAY on the replica socket after SYNC?
+#
+# If you select "yes" Redis will use a smaller number of TCP packets and
+# less bandwidth to send data to replicas. But this can add a delay for
+# the data to appear on the replica side, up to 40 milliseconds with
+# Linux kernels using a default configuration.
+#
+# If you select "no" the delay for data to appear on the replica side will
+# be reduced but more bandwidth will be used for replication.
+#
+# By default we optimize for low latency, but in very high traffic conditions
+# or when the master and replicas are many hops away, turning this to "yes" may
+# be a good idea.
+repl-disable-tcp-nodelay no
+
+# Set the replication backlog size. The backlog is a buffer that accumulates
+# replica data when replicas are disconnected for some time, so that when a replica
+# wants to reconnect again, often a full resync is not needed, but a partial
+# resync is enough, just passing the portion of data the replica missed while
+# disconnected.
+#
+# The bigger the replication backlog, the longer the time the replica can be
+# disconnected and later be able to perform a partial resynchronization.
+#
+# The backlog is only allocated once there is at least a replica connected.
+#
+# repl-backlog-size 1mb
+
+# After a master has no longer connected replicas for some time, the backlog
+# will be freed. The following option configures the amount of seconds that
+# need to elapse, starting from the time the last replica disconnected, for
+# the backlog buffer to be freed.
+#
+# Note that replicas never free the backlog for timeout, since they may be
+# promoted to masters later, and should be able to correctly "partially
+# resynchronize" with the replicas: hence they should always accumulate backlog.
+#
+# A value of 0 means to never release the backlog.
+#
+# repl-backlog-ttl 3600
+
+# The replica priority is an integer number published by Redis in the INFO output.
+# It is used by Redis Sentinel in order to select a replica to promote into a
+# master if the master is no longer working correctly.
+#
+# A replica with a low priority number is considered better for promotion, so
+# for instance if there are three replicas with priority 10, 100, 25 Sentinel will
+# pick the one with priority 10, that is the lowest.
+#
+# However a special priority of 0 marks the replica as not able to perform the
+# role of master, so a replica with priority of 0 will never be selected by
+# Redis Sentinel for promotion.
+#
+# By default the priority is 100.
+replica-priority 100
+
+# It is possible for a master to stop accepting writes if there are less than
+# N replicas connected, having a lag less or equal than M seconds.
+#
+# The N replicas need to be in "online" state.
+#
+# The lag in seconds, that must be <= the specified value, is calculated from
+# the last ping received from the replica, that is usually sent every second.
+#
+# This option does not GUARANTEE that N replicas will accept the write, but
+# will limit the window of exposure for lost writes in case not enough replicas
+# are available, to the specified number of seconds.
+#
+# For example to require at least 3 replicas with a lag <= 10 seconds use:
+#
+# min-replicas-to-write 3
+# min-replicas-max-lag 10
+#
+# Setting one or the other to 0 disables the feature.
+#
+# By default min-replicas-to-write is set to 0 (feature disabled) and
+# min-replicas-max-lag is set to 10.
+
+# A Redis master is able to list the address and port of the attached
+# replicas in different ways. For example the "INFO replication" section
+# offers this information, which is used, among other tools, by
+# Redis Sentinel in order to discover replica instances.
+# Another place where this info is available is in the output of the
+# "ROLE" command of a master.
+#
+# The listed IP and address normally reported by a replica is obtained
+# in the following way:
+#
+#   IP: The address is auto detected by checking the peer address
+#   of the socket used by the replica to connect with the master.
+#
+#   Port: The port is communicated by the replica during the replication
+#   handshake, and is normally the port that the replica is using to
+#   listen for connections.
+#
+# However when port forwarding or Network Address Translation (NAT) is
+# used, the replica may be actually reachable via different IP and port
+# pairs. The following two options can be used by a replica in order to
+# report to its master a specific set of IP and port, so that both INFO
+# and ROLE will report those values.
+#
+# There is no need to use both the options if you need to override just
+# the port or the IP address.
+#
+# replica-announce-ip 5.5.5.5
+# replica-announce-port 1234
+
+################################## SECURITY ###################################
+
+# Require clients to issue AUTH <PASSWORD> before processing any other
+# commands.  This might be useful in environments in which you do not trust
+# others with access to the host running redis-server.
+#
+# This should stay commented out for backward compatibility and because most
+# people do not need auth (e.g. they run their own servers).
+#
+# Warning: since Redis is pretty fast an outside user can try up to
+# 150k passwords per second against a good box. This means that you should
+# use a very strong password otherwise it will be very easy to break.
+#
+requirepass mypassword
+
+# Command renaming.
+#
+# It is possible to change the name of dangerous commands in a shared
+# environment. For instance the CONFIG command may be renamed into something
+# hard to guess so that it will still be available for internal-use tools
+# but not available for general clients.
+#
+# Example:
+#
+# rename-command CONFIG b840fc02d524045429941cc15f59e41cb7be6c52
+#
+# It is also possible to completely kill a command by renaming it into
+# an empty string:
+#
+# rename-command CONFIG ""
+#
+# Please note that changing the name of commands that are logged into the
+# AOF file or transmitted to replicas may cause problems.
+
+################################### CLIENTS ####################################
+
+# Set the max number of connected clients at the same time. By default
+# this limit is set to 10000 clients, however if the Redis server is not
+# able to configure the process file limit to allow for the specified limit
+# the max number of allowed clients is set to the current file limit
+# minus 32 (as Redis reserves a few file descriptors for internal uses).
+#
+# Once the limit is reached Redis will close all the new connections sending
+# an error 'max number of clients reached'.
+#
+# maxclients 10000
+
+############################## MEMORY MANAGEMENT ################################
+
+# Set a memory usage limit to the specified amount of bytes.
+# When the memory limit is reached Redis will try to remove keys
+# according to the eviction policy selected (see maxmemory-policy).
+#
+# If Redis can't remove keys according to the policy, or if the policy is
+# set to 'noeviction', Redis will start to reply with errors to commands
+# that would use more memory, like SET, LPUSH, and so on, and will continue
+# to reply to read-only commands like GET.
+#
+# This option is usually useful when using Redis as an LRU or LFU cache, or to
+# set a hard memory limit for an instance (using the 'noeviction' policy).
+#
+# WARNING: If you have replicas attached to an instance with maxmemory on,
+# the size of the output buffers needed to feed the replicas are subtracted
+# from the used memory count, so that network problems / resyncs will
+# not trigger a loop where keys are evicted, and in turn the output
+# buffer of replicas is full with DELs of keys evicted triggering the deletion
+# of more keys, and so forth until the database is completely emptied.
+#
+# In short... if you have replicas attached it is suggested that you set a lower
+# limit for maxmemory so that there is some free RAM on the system for replica
+# output buffers (but this is not needed if the policy is 'noeviction').
+#
+# maxmemory <bytes>
+
+# MAXMEMORY POLICY: how Redis will select what to remove when maxmemory
+# is reached. You can select among five behaviors:
+#
+# volatile-lru -> Evict using approximated LRU among the keys with an expire set.
+# allkeys-lru -> Evict any key using approximated LRU.
+# volatile-lfu -> Evict using approximated LFU among the keys with an expire set.
+# allkeys-lfu -> Evict any key using approximated LFU.
+# volatile-random -> Remove a random key among the ones with an expire set.
+# allkeys-random -> Remove a random key, any key.
+# volatile-ttl -> Remove the key with the nearest expire time (minor TTL)
+# noeviction -> Don't evict anything, just return an error on write operations.
+#
+# LRU means Least Recently Used
+# LFU means Least Frequently Used
+#
+# Both LRU, LFU and volatile-ttl are implemented using approximated
+# randomized algorithms.
+#
+# Note: with any of the above policies, Redis will return an error on write
+#       operations, when there are no suitable keys for eviction.
+#
+#       At the date of writing these commands are: set setnx setex append
+#       incr decr rpush lpush rpushx lpushx linsert lset rpoplpush sadd
+#       sinter sinterstore sunion sunionstore sdiff sdiffstore zadd zincrby
+#       zunionstore zinterstore hset hsetnx hmset hincrby incrby decrby
+#       getset mset msetnx exec sort
+#
+# The default is:
+#
+# maxmemory-policy noeviction
+
+# LRU, LFU and minimal TTL algorithms are not precise algorithms but approximated
+# algorithms (in order to save memory), so you can tune it for speed or
+# accuracy. For default Redis will check five keys and pick the one that was
+# used less recently, you can change the sample size using the following
+# configuration directive.
+#
+# The default of 5 produces good enough results. 10 Approximates very closely
+# true LRU but costs more CPU. 3 is faster but not very accurate.
+#
+# maxmemory-samples 5
+
+# Starting from Redis 5, by default a replica will ignore its maxmemory setting
+# (unless it is promoted to master after a failover or manually). It means
+# that the eviction of keys will be just handled by the master, sending the
+# DEL commands to the replica as keys evict in the master side.
+#
+# This behavior ensures that masters and replicas stay consistent, and is usually
+# what you want, however if your replica is writable, or you want the replica to have
+# a different memory setting, and you are sure all the writes performed to the
+# replica are idempotent, then you may change this default (but be sure to understand
+# what you are doing).
+#
+# Note that since the replica by default does not evict, it may end using more
+# memory than the one set via maxmemory (there are certain buffers that may
+# be larger on the replica, or data structures may sometimes take more memory and so
+# forth). So make sure you monitor your replicas and make sure they have enough
+# memory to never hit a real out-of-memory condition before the master hits
+# the configured maxmemory setting.
+#
+# replica-ignore-maxmemory yes
+
+############################# LAZY FREEING ####################################
+
+# Redis has two primitives to delete keys. One is called DEL and is a blocking
+# deletion of the object. It means that the server stops processing new commands
+# in order to reclaim all the memory associated with an object in a synchronous
+# way. If the key deleted is associated with a small object, the time needed
+# in order to execute the DEL command is very small and comparable to most other
+# O(1) or O(log_N) commands in Redis. However if the key is associated with an
+# aggregated value containing millions of elements, the server can block for
+# a long time (even seconds) in order to complete the operation.
+#
+# For the above reasons Redis also offers non blocking deletion primitives
+# such as UNLINK (non blocking DEL) and the ASYNC option of FLUSHALL and
+# FLUSHDB commands, in order to reclaim memory in background. Those commands
+# are executed in constant time. Another thread will incrementally free the
+# object in the background as fast as possible.
+#
+# DEL, UNLINK and ASYNC option of FLUSHALL and FLUSHDB are user-controlled.
+# It's up to the design of the application to understand when it is a good
+# idea to use one or the other. However the Redis server sometimes has to
+# delete keys or flush the whole database as a side effect of other operations.
+# Specifically Redis deletes objects independently of a user call in the
+# following scenarios:
+#
+# 1) On eviction, because of the maxmemory and maxmemory policy configurations,
+#    in order to make room for new data, without going over the specified
+#    memory limit.
+# 2) Because of expire: when a key with an associated time to live (see the
+#    EXPIRE command) must be deleted from memory.
+# 3) Because of a side effect of a command that stores data on a key that may
+#    already exist. For example the RENAME command may delete the old key
+#    content when it is replaced with another one. Similarly SUNIONSTORE
+#    or SORT with STORE option may delete existing keys. The SET command
+#    itself removes any old content of the specified key in order to replace
+#    it with the specified string.
+# 4) During replication, when a replica performs a full resynchronization with
+#    its master, the content of the whole database is removed in order to
+#    load the RDB file just transferred.
+#
+# In all the above cases the default is to delete objects in a blocking way,
+# like if DEL was called. However you can configure each case specifically
+# in order to instead release memory in a non-blocking way like if UNLINK
+# was called, using the following configuration directives:
+
+lazyfree-lazy-eviction no
+lazyfree-lazy-expire no
+lazyfree-lazy-server-del no
+replica-lazy-flush no
+
+############################## APPEND ONLY MODE ###############################
+
+# By default Redis asynchronously dumps the dataset on disk. This mode is
+# good enough in many applications, but an issue with the Redis process or
+# a power outage may result into a few minutes of writes lost (depending on
+# the configured save points).
+#
+# The Append Only File is an alternative persistence mode that provides
+# much better durability. For instance using the default data fsync policy
+# (see later in the config file) Redis can lose just one second of writes in a
+# dramatic event like a server power outage, or a single write if something
+# wrong with the Redis process itself happens, but the operating system is
+# still running correctly.
+#
+# AOF and RDB persistence can be enabled at the same time without problems.
+# If the AOF is enabled on startup Redis will load the AOF, that is the file
+# with the better durability guarantees.
+#
+# Please check http://redis.io/topics/persistence for more information.
+
+appendonly no
+
+# The name of the append only file (default: "appendonly.aof")
+
+appendfilename "appendonly.aof"
+
+# The fsync() call tells the Operating System to actually write data on disk
+# instead of waiting for more data in the output buffer. Some OS will really flush
+# data on disk, some other OS will just try to do it ASAP.
+#
+# Redis supports three different modes:
+#
+# no: don't fsync, just let the OS flush the data when it wants. Faster.
+# always: fsync after every write to the append only log. Slow, Safest.
+# everysec: fsync only one time every second. Compromise.
+#
+# The default is "everysec", as that's usually the right compromise between
+# speed and data safety. It's up to you to understand if you can relax this to
+# "no" that will let the operating system flush the output buffer when
+# it wants, for better performances (but if you can live with the idea of
+# some data loss consider the default persistence mode that's snapshotting),
+# or on the contrary, use "always" that's very slow but a bit safer than
+# everysec.
+#
+# More details please check the following article:
+# http://antirez.com/post/redis-persistence-demystified.html
+#
+# If unsure, use "everysec".
+
+# appendfsync always
+appendfsync everysec
+# appendfsync no
+
+# When the AOF fsync policy is set to always or everysec, and a background
+# saving process (a background save or AOF log background rewriting) is
+# performing a lot of I/O against the disk, in some Linux configurations
+# Redis may block too long on the fsync() call. Note that there is no fix for
+# this currently, as even performing fsync in a different thread will block
+# our synchronous write(2) call.
+#
+# In order to mitigate this problem it's possible to use the following option
+# that will prevent fsync() from being called in the main process while a
+# BGSAVE or BGREWRITEAOF is in progress.
+#
+# This means that while another child is saving, the durability of Redis is
+# the same as "appendfsync none". In practical terms, this means that it is
+# possible to lose up to 30 seconds of log in the worst scenario (with the
+# default Linux settings).
+#
+# If you have latency problems turn this to "yes". Otherwise leave it as
+# "no" that is the safest pick from the point of view of durability.
+
+no-appendfsync-on-rewrite no
+
+# Automatic rewrite of the append only file.
+# Redis is able to automatically rewrite the log file implicitly calling
+# BGREWRITEAOF when the AOF log size grows by the specified percentage.
+#
+# This is how it works: Redis remembers the size of the AOF file after the
+# latest rewrite (if no rewrite has happened since the restart, the size of
+# the AOF at startup is used).
+#
+# This base size is compared to the current size. If the current size is
+# bigger than the specified percentage, the rewrite is triggered. Also
+# you need to specify a minimal size for the AOF file to be rewritten, this
+# is useful to avoid rewriting the AOF file even if the percentage increase
+# is reached but it is still pretty small.
+#
+# Specify a percentage of zero in order to disable the automatic AOF
+# rewrite feature.
+
+auto-aof-rewrite-percentage 100
+auto-aof-rewrite-min-size 64mb
+
+# An AOF file may be found to be truncated at the end during the Redis
+# startup process, when the AOF data gets loaded back into memory.
+# This may happen when the system where Redis is running
+# crashes, especially when an ext4 filesystem is mounted without the
+# data=ordered option (however this can't happen when Redis itself
+# crashes or aborts but the operating system still works correctly).
+#
+# Redis can either exit with an error when this happens, or load as much
+# data as possible (the default now) and start if the AOF file is found
+# to be truncated at the end. The following option controls this behavior.
+#
+# If aof-load-truncated is set to yes, a truncated AOF file is loaded and
+# the Redis server starts emitting a log to inform the user of the event.
+# Otherwise if the option is set to no, the server aborts with an error
+# and refuses to start. When the option is set to no, the user requires
+# to fix the AOF file using the "redis-check-aof" utility before to restart
+# the server.
+#
+# Note that if the AOF file will be found to be corrupted in the middle
+# the server will still exit with an error. This option only applies when
+# Redis will try to read more data from the AOF file but not enough bytes
+# will be found.
+aof-load-truncated yes
+
+# When rewriting the AOF file, Redis is able to use an RDB preamble in the
+# AOF file for faster rewrites and recoveries. When this option is turned
+# on the rewritten AOF file is composed of two different stanzas:
+#
+#   [RDB file][AOF tail]
+#
+# When loading Redis recognizes that the AOF file starts with the "REDIS"
+# string and loads the prefixed RDB file, and continues loading the AOF
+# tail.
+aof-use-rdb-preamble yes
+
+################################ LUA SCRIPTING  ###############################
+
+# Max execution time of a Lua script in milliseconds.
+#
+# If the maximum execution time is reached Redis will log that a script is
+# still in execution after the maximum allowed time and will start to
+# reply to queries with an error.
+#
+# When a long running script exceeds the maximum execution time only the
+# SCRIPT KILL and SHUTDOWN NOSAVE commands are available. The first can be
+# used to stop a script that did not yet called write commands. The second
+# is the only way to shut down the server in the case a write command was
+# already issued by the script but the user doesn't want to wait for the natural
+# termination of the script.
+#
+# Set it to 0 or a negative value for unlimited execution without warnings.
+lua-time-limit 5000
+
+################################ REDIS CLUSTER  ###############################
+
+# Normal Redis instances can't be part of a Redis Cluster; only nodes that are
+# started as cluster nodes can. In order to start a Redis instance as a
+# cluster node enable the cluster support uncommenting the following:
+#
+# cluster-enabled yes
+
+# Every cluster node has a cluster configuration file. This file is not
+# intended to be edited by hand. It is created and updated by Redis nodes.
+# Every Redis Cluster node requires a different cluster configuration file.
+# Make sure that instances running in the same system do not have
+# overlapping cluster configuration file names.
+#
+# cluster-config-file nodes-6379.conf
+
+# Cluster node timeout is the amount of milliseconds a node must be unreachable
+# for it to be considered in failure state.
+# Most other internal time limits are multiple of the node timeout.
+#
+# cluster-node-timeout 15000
+
+# A replica of a failing master will avoid to start a failover if its data
+# looks too old.
+#
+# There is no simple way for a replica to actually have an exact measure of
+# its "data age", so the following two checks are performed:
+#
+# 1) If there are multiple replicas able to failover, they exchange messages
+#    in order to try to give an advantage to the replica with the best
+#    replication offset (more data from the master processed).
+#    Replicas will try to get their rank by offset, and apply to the start
+#    of the failover a delay proportional to their rank.
+#
+# 2) Every single replica computes the time of the last interaction with
+#    its master. This can be the last ping or command received (if the master
+#    is still in the "connected" state), or the time that elapsed since the
+#    disconnection with the master (if the replication link is currently down).
+#    If the last interaction is too old, the replica will not try to failover
+#    at all.
+#
+# The point "2" can be tuned by user. Specifically a replica will not perform
+# the failover if, since the last interaction with the master, the time
+# elapsed is greater than:
+#
+#   (node-timeout * replica-validity-factor) + repl-ping-replica-period
+#
+# So for example if node-timeout is 30 seconds, and the replica-validity-factor
+# is 10, and assuming a default repl-ping-replica-period of 10 seconds, the
+# replica will not try to failover if it was not able to talk with the master
+# for longer than 310 seconds.
+#
+# A large replica-validity-factor may allow replicas with too old data to failover
+# a master, while a too small value may prevent the cluster from being able to
+# elect a replica at all.
+#
+# For maximum availability, it is possible to set the replica-validity-factor
+# to a value of 0, which means, that replicas will always try to failover the
+# master regardless of the last time they interacted with the master.
+# (However they'll always try to apply a delay proportional to their
+# offset rank).
+#
+# Zero is the only value able to guarantee that when all the partitions heal
+# the cluster will always be able to continue.
+#
+# cluster-replica-validity-factor 10
+
+# Cluster replicas are able to migrate to orphaned masters, that are masters
+# that are left without working replicas. This improves the cluster ability
+# to resist to failures as otherwise an orphaned master can't be failed over
+# in case of failure if it has no working replicas.
+#
+# Replicas migrate to orphaned masters only if there are still at least a
+# given number of other working replicas for their old master. This number
+# is the "migration barrier". A migration barrier of 1 means that a replica
+# will migrate only if there is at least 1 other working replica for its master
+# and so forth. It usually reflects the number of replicas you want for every
+# master in your cluster.
+#
+# Default is 1 (replicas migrate only if their masters remain with at least
+# one replica). To disable migration just set it to a very large value.
+# A value of 0 can be set but is useful only for debugging and dangerous
+# in production.
+#
+# cluster-migration-barrier 1
+
+# By default Redis Cluster nodes stop accepting queries if they detect there
+# is at least an hash slot uncovered (no available node is serving it).
+# This way if the cluster is partially down (for example a range of hash slots
+# are no longer covered) all the cluster becomes, eventually, unavailable.
+# It automatically returns available as soon as all the slots are covered again.
+#
+# However sometimes you want the subset of the cluster which is working,
+# to continue to accept queries for the part of the key space that is still
+# covered. In order to do so, just set the cluster-require-full-coverage
+# option to no.
+#
+# cluster-require-full-coverage yes
+
+# This option, when set to yes, prevents replicas from trying to failover its
+# master during master failures. However the master can still perform a
+# manual failover, if forced to do so.
+#
+# This is useful in different scenarios, especially in the case of multiple
+# data center operations, where we want one side to never be promoted if not
+# in the case of a total DC failure.
+#
+# cluster-replica-no-failover no
+
+# In order to setup your cluster make sure to read the documentation
+# available at http://redis.io web site.
+
+########################## CLUSTER DOCKER/NAT support  ########################
+
+# In certain deployments, Redis Cluster nodes address discovery fails, because
+# addresses are NAT-ted or because ports are forwarded (the typical case is
+# Docker and other containers).
+#
+# In order to make Redis Cluster working in such environments, a static
+# configuration where each node knows its public address is needed. The
+# following two options are used for this scope, and are:
+#
+# * cluster-announce-ip
+# * cluster-announce-port
+# * cluster-announce-bus-port
+#
+# Each instruct the node about its address, client port, and cluster message
+# bus port. The information is then published in the header of the bus packets
+# so that other nodes will be able to correctly map the address of the node
+# publishing the information.
+#
+# If the above options are not used, the normal Redis Cluster auto-detection
+# will be used instead.
+#
+# Note that when remapped, the bus port may not be at the fixed offset of
+# clients port + 10000, so you can specify any port and bus-port depending
+# on how they get remapped. If the bus-port is not set, a fixed offset of
+# 10000 will be used as usually.
+#
+# Example:
+#
+# cluster-announce-ip 10.1.1.5
+# cluster-announce-port 6379
+# cluster-announce-bus-port 6380
+
+################################## SLOW LOG ###################################
+
+# The Redis Slow Log is a system to log queries that exceeded a specified
+# execution time. The execution time does not include the I/O operations
+# like talking with the client, sending the reply and so forth,
+# but just the time needed to actually execute the command (this is the only
+# stage of command execution where the thread is blocked and can not serve
+# other requests in the meantime).
+#
+# You can configure the slow log with two parameters: one tells Redis
+# what is the execution time, in microseconds, to exceed in order for the
+# command to get logged, and the other parameter is the length of the
+# slow log. When a new command is logged the oldest one is removed from the
+# queue of logged commands.
+
+# The following time is expressed in microseconds, so 1000000 is equivalent
+# to one second. Note that a negative number disables the slow log, while
+# a value of zero forces the logging of every command.
+slowlog-log-slower-than 10000
+
+# There is no limit to this length. Just be aware that it will consume memory.
+# You can reclaim memory used by the slow log with SLOWLOG RESET.
+slowlog-max-len 128
+
+################################ LATENCY MONITOR ##############################
+
+# The Redis latency monitoring subsystem samples different operations
+# at runtime in order to collect data related to possible sources of
+# latency of a Redis instance.
+#
+# Via the LATENCY command this information is available to the user that can
+# print graphs and obtain reports.
+#
+# The system only logs operations that were performed in a time equal or
+# greater than the amount of milliseconds specified via the
+# latency-monitor-threshold configuration directive. When its value is set
+# to zero, the latency monitor is turned off.
+#
+# By default latency monitoring is disabled since it is mostly not needed
+# if you don't have latency issues, and collecting data has a performance
+# impact, that while very small, can be measured under big load. Latency
+# monitoring can easily be enabled at runtime using the command
+# "CONFIG SET latency-monitor-threshold <milliseconds>" if needed.
+latency-monitor-threshold 0
+
+############################# EVENT NOTIFICATION ##############################
+
+# Redis can notify Pub/Sub clients about events happening in the key space.
+# This feature is documented at http://redis.io/topics/notifications
+#
+# For instance if keyspace events notification is enabled, and a client
+# performs a DEL operation on key "foo" stored in the Database 0, two
+# messages will be published via Pub/Sub:
+#
+# PUBLISH __keyspace@0__:foo del
+# PUBLISH __keyevent@0__:del foo
+#
+# It is possible to select the events that Redis will notify among a set
+# of classes. Every class is identified by a single character:
+#
+#  K     Keyspace events, published with __keyspace@<db>__ prefix.
+#  E     Keyevent events, published with __keyevent@<db>__ prefix.
+#  g     Generic commands (non-type specific) like DEL, EXPIRE, RENAME, ...
+#  $     String commands
+#  l     List commands
+#  s     Set commands
+#  h     Hash commands
+#  z     Sorted set commands
+#  x     Expired events (events generated every time a key expires)
+#  e     Evicted events (events generated when a key is evicted for maxmemory)
+#  A     Alias for g$lshzxe, so that the "AKE" string means all the events.
+#
+#  The "notify-keyspace-events" takes as argument a string that is composed
+#  of zero or multiple characters. The empty string means that notifications
+#  are disabled.
+#
+#  Example: to enable list and generic events, from the point of view of the
+#           event name, use:
+#
+#  notify-keyspace-events Elg
+#
+#  Example 2: to get the stream of the expired keys subscribing to channel
+#             name __keyevent@0__:expired use:
+#
+#  notify-keyspace-events Ex
+#
+#  By default all notifications are disabled because most users don't need
+#  this feature and the feature has some overhead. Note that if you don't
+#  specify at least one of K or E, no events will be delivered.
+notify-keyspace-events ""
+
+############################### ADVANCED CONFIG ###############################
+
+# Hashes are encoded using a memory efficient data structure when they have a
+# small number of entries, and the biggest entry does not exceed a given
+# threshold. These thresholds can be configured using the following directives.
+hash-max-ziplist-entries 512
+hash-max-ziplist-value 64
+
+# Lists are also encoded in a special way to save a lot of space.
+# The number of entries allowed per internal list node can be specified
+# as a fixed maximum size or a maximum number of elements.
+# For a fixed maximum size, use -5 through -1, meaning:
+# -5: max size: 64 Kb  <-- not recommended for normal workloads
+# -4: max size: 32 Kb  <-- not recommended
+# -3: max size: 16 Kb  <-- probably not recommended
+# -2: max size: 8 Kb   <-- good
+# -1: max size: 4 Kb   <-- good
+# Positive numbers mean store up to _exactly_ that number of elements
+# per list node.
+# The highest performing option is usually -2 (8 Kb size) or -1 (4 Kb size),
+# but if your use case is unique, adjust the settings as necessary.
+list-max-ziplist-size -2
+
+# Lists may also be compressed.
+# Compress depth is the number of quicklist ziplist nodes from *each* side of
+# the list to *exclude* from compression.  The head and tail of the list
+# are always uncompressed for fast push/pop operations.  Settings are:
+# 0: disable all list compression
+# 1: depth 1 means "don't start compressing until after 1 node into the list,
+#    going from either the head or tail"
+#    So: [head]->node->node->...->node->[tail]
+#    [head], [tail] will always be uncompressed; inner nodes will compress.
+# 2: [head]->[next]->node->node->...->node->[prev]->[tail]
+#    2 here means: don't compress head or head->next or tail->prev or tail,
+#    but compress all nodes between them.
+# 3: [head]->[next]->[next]->node->node->...->node->[prev]->[prev]->[tail]
+# etc.
+list-compress-depth 0
+
+# Sets have a special encoding in just one case: when a set is composed
+# of just strings that happen to be integers in radix 10 in the range
+# of 64 bit signed integers.
+# The following configuration setting sets the limit in the size of the
+# set in order to use this special memory saving encoding.
+set-max-intset-entries 512
+
+# Similarly to hashes and lists, sorted sets are also specially encoded in
+# order to save a lot of space. This encoding is only used when the length and
+# elements of a sorted set are below the following limits:
+zset-max-ziplist-entries 128
+zset-max-ziplist-value 64
+
+# HyperLogLog sparse representation bytes limit. The limit includes the
+# 16 bytes header. When an HyperLogLog using the sparse representation crosses
+# this limit, it is converted into the dense representation.
+#
+# A value greater than 16000 is totally useless, since at that point the
+# dense representation is more memory efficient.
+#
+# The suggested value is ~ 3000 in order to have the benefits of
+# the space efficient encoding without slowing down too much PFADD,
+# which is O(N) with the sparse encoding. The value can be raised to
+# ~ 10000 when CPU is not a concern, but space is, and the data set is
+# composed of many HyperLogLogs with cardinality in the 0 - 15000 range.
+hll-sparse-max-bytes 3000
+
+# Streams macro node max size / items. The stream data structure is a radix
+# tree of big nodes that encode multiple items inside. Using this configuration
+# it is possible to configure how big a single node can be in bytes, and the
+# maximum number of items it may contain before switching to a new node when
+# appending new stream entries. If any of the following settings are set to
+# zero, the limit is ignored, so for instance it is possible to set just a
+# max entires limit by setting max-bytes to 0 and max-entries to the desired
+# value.
+stream-node-max-bytes 4096
+stream-node-max-entries 100
+
+# Active rehashing uses 1 millisecond every 100 milliseconds of CPU time in
+# order to help rehashing the main Redis hash table (the one mapping top-level
+# keys to values). The hash table implementation Redis uses (see dict.c)
+# performs a lazy rehashing: the more operation you run into a hash table
+# that is rehashing, the more rehashing "steps" are performed, so if the
+# server is idle the rehashing is never complete and some more memory is used
+# by the hash table.
+#
+# The default is to use this millisecond 10 times every second in order to
+# actively rehash the main dictionaries, freeing memory when possible.
+#
+# If unsure:
+# use "activerehashing no" if you have hard latency requirements and it is
+# not a good thing in your environment that Redis can reply from time to time
+# to queries with 2 milliseconds delay.
+#
+# use "activerehashing yes" if you don't have such hard requirements but
+# want to free memory asap when possible.
+activerehashing yes
+
+# The client output buffer limits can be used to force disconnection of clients
+# that are not reading data from the server fast enough for some reason (a
+# common reason is that a Pub/Sub client can't consume messages as fast as the
+# publisher can produce them).
+#
+# The limit can be set differently for the three different classes of clients:
+#
+# normal -> normal clients including MONITOR clients
+# replica  -> replica clients
+# pubsub -> clients subscribed to at least one pubsub channel or pattern
+#
+# The syntax of every client-output-buffer-limit directive is the following:
+#
+# client-output-buffer-limit <class> <hard limit> <soft limit> <soft seconds>
+#
+# A client is immediately disconnected once the hard limit is reached, or if
+# the soft limit is reached and remains reached for the specified number of
+# seconds (continuously).
+# So for instance if the hard limit is 32 megabytes and the soft limit is
+# 16 megabytes / 10 seconds, the client will get disconnected immediately
+# if the size of the output buffers reach 32 megabytes, but will also get
+# disconnected if the client reaches 16 megabytes and continuously overcomes
+# the limit for 10 seconds.
+#
+# By default normal clients are not limited because they don't receive data
+# without asking (in a push way), but just after a request, so only
+# asynchronous clients may create a scenario where data is requested faster
+# than it can read.
+#
+# Instead there is a default limit for pubsub and replica clients, since
+# subscribers and replicas receive data in a push fashion.
+#
+# Both the hard or the soft limit can be disabled by setting them to zero.
+client-output-buffer-limit normal 0 0 0
+client-output-buffer-limit replica 256mb 64mb 60
+client-output-buffer-limit pubsub 32mb 8mb 60
+
+# Client query buffers accumulate new commands. They are limited to a fixed
+# amount by default in order to avoid that a protocol desynchronization (for
+# instance due to a bug in the client) will lead to unbound memory usage in
+# the query buffer. However you can configure it here if you have very special
+# needs, such us huge multi/exec requests or alike.
+#
+# client-query-buffer-limit 1gb
+
+# In the Redis protocol, bulk requests, that are, elements representing single
+# strings, are normally limited ot 512 mb. However you can change this limit
+# here.
+#
+# proto-max-bulk-len 512mb
+
+# Redis calls an internal function to perform many background tasks, like
+# closing connections of clients in timeout, purging expired keys that are
+# never requested, and so forth.
+#
+# Not all tasks are performed with the same frequency, but Redis checks for
+# tasks to perform according to the specified "hz" value.
+#
+# By default "hz" is set to 10. Raising the value will use more CPU when
+# Redis is idle, but at the same time will make Redis more responsive when
+# there are many keys expiring at the same time, and timeouts may be
+# handled with more precision.
+#
+# The range is between 1 and 500, however a value over 100 is usually not
+# a good idea. Most users should use the default of 10 and raise this up to
+# 100 only in environments where very low latency is required.
+hz 10
+
+# Normally it is useful to have an HZ value which is proportional to the
+# number of clients connected. This is useful in order, for instance, to
+# avoid too many clients are processed for each background task invocation
+# in order to avoid latency spikes.
+#
+# Since the default HZ value by default is conservatively set to 10, Redis
+# offers, and enables by default, the ability to use an adaptive HZ value
+# which will temporary raise when there are many connected clients.
+#
+# When dynamic HZ is enabled, the actual configured HZ will be used as
+# as a baseline, but multiples of the configured HZ value will be actually
+# used as needed once more clients are connected. In this way an idle
+# instance will use very little CPU time while a busy instance will be
+# more responsive.
+dynamic-hz yes
+
+# When a child rewrites the AOF file, if the following option is enabled
+# the file will be fsync-ed every 32 MB of data generated. This is useful
+# in order to commit the file to the disk more incrementally and avoid
+# big latency spikes.
+aof-rewrite-incremental-fsync yes
+
+# When redis saves RDB file, if the following option is enabled
+# the file will be fsync-ed every 32 MB of data generated. This is useful
+# in order to commit the file to the disk more incrementally and avoid
+# big latency spikes.
+rdb-save-incremental-fsync yes
+
+# Redis LFU eviction (see maxmemory setting) can be tuned. However it is a good
+# idea to start with the default settings and only change them after investigating
+# how to improve the performances and how the keys LFU change over time, which
+# is possible to inspect via the OBJECT FREQ command.
+#
+# There are two tunable parameters in the Redis LFU implementation: the
+# counter logarithm factor and the counter decay time. It is important to
+# understand what the two parameters mean before changing them.
+#
+# The LFU counter is just 8 bits per key, it's maximum value is 255, so Redis
+# uses a probabilistic increment with logarithmic behavior. Given the value
+# of the old counter, when a key is accessed, the counter is incremented in
+# this way:
+#
+# 1. A random number R between 0 and 1 is extracted.
+# 2. A probability P is calculated as 1/(old_value*lfu_log_factor+1).
+# 3. The counter is incremented only if R < P.
+#
+# The default lfu-log-factor is 10. This is a table of how the frequency
+# counter changes with a different number of accesses with different
+# logarithmic factors:
+#
+# +--------+------------+------------+------------+------------+------------+
+# | factor | 100 hits   | 1000 hits  | 100K hits  | 1M hits    | 10M hits   |
+# +--------+------------+------------+------------+------------+------------+
+# | 0      | 104        | 255        | 255        | 255        | 255        |
+# +--------+------------+------------+------------+------------+------------+
+# | 1      | 18         | 49         | 255        | 255        | 255        |
+# +--------+------------+------------+------------+------------+------------+
+# | 10     | 10         | 18         | 142        | 255        | 255        |
+# +--------+------------+------------+------------+------------+------------+
+# | 100    | 8          | 11         | 49         | 143        | 255        |
+# +--------+------------+------------+------------+------------+------------+
+#
+# NOTE: The above table was obtained by running the following commands:
+#
+#   redis-benchmark -n 1000000 incr foo
+#   redis-cli object freq foo
+#
+# NOTE 2: The counter initial value is 5 in order to give new objects a chance
+# to accumulate hits.
+#
+# The counter decay time is the time, in minutes, that must elapse in order
+# for the key counter to be divided by two (or decremented if it has a value
+# less <= 10).
+#
+# The default value for the lfu-decay-time is 1. A Special value of 0 means to
+# decay the counter every time it happens to be scanned.
+#
+# lfu-log-factor 10
+# lfu-decay-time 1
+
+########################### ACTIVE DEFRAGMENTATION #######################
+#
+# WARNING THIS FEATURE IS EXPERIMENTAL. However it was stress tested
+# even in production and manually tested by multiple engineers for some
+# time.
+#
+# What is active defragmentation?
+# -------------------------------
+#
+# Active (online) defragmentation allows a Redis server to compact the
+# spaces left between small allocations and deallocations of data in memory,
+# thus allowing to reclaim back memory.
+#
+# Fragmentation is a natural process that happens with every allocator (but
+# less so with Jemalloc, fortunately) and certain workloads. Normally a server
+# restart is needed in order to lower the fragmentation, or at least to flush
+# away all the data and create it again. However thanks to this feature
+# implemented by Oran Agra for Redis 4.0 this process can happen at runtime
+# in an "hot" way, while the server is running.
+#
+# Basically when the fragmentation is over a certain level (see the
+# configuration options below) Redis will start to create new copies of the
+# values in contiguous memory regions by exploiting certain specific Jemalloc
+# features (in order to understand if an allocation is causing fragmentation
+# and to allocate it in a better place), and at the same time, will release the
+# old copies of the data. This process, repeated incrementally for all the keys
+# will cause the fragmentation to drop back to normal values.
+#
+# Important things to understand:
+#
+# 1. This feature is disabled by default, and only works if you compiled Redis
+#    to use the copy of Jemalloc we ship with the source code of Redis.
+#    This is the default with Linux builds.
+#
+# 2. You never need to enable this feature if you don't have fragmentation
+#    issues.
+#
+# 3. Once you experience fragmentation, you can enable this feature when
+#    needed with the command "CONFIG SET activedefrag yes".
+#
+# The configuration parameters are able to fine tune the behavior of the
+# defragmentation process. If you are not sure about what they mean it is
+# a good idea to leave the defaults untouched.
+
+# Enabled active defragmentation
+# activedefrag yes
+
+# Minimum amount of fragmentation waste to start active defrag
+# active-defrag-ignore-bytes 100mb
+
+# Minimum percentage of fragmentation to start active defrag
+# active-defrag-threshold-lower 10
+
+# Maximum percentage of fragmentation at which we use maximum effort
+# active-defrag-threshold-upper 100
+
+# Minimal effort for defrag in CPU percentage
+# active-defrag-cycle-min 5
+
+# Maximal effort for defrag in CPU percentage
+# active-defrag-cycle-max 75
+
+# Maximum number of set/hash/zset/list fields that will be processed from
+# the main dictionary scan
+# active-defrag-max-scan-fields 1000
+
diff --git a/examples/docker-compose.yml b/examples/docker-compose.yml
 new file mode 100644
index 0000000..0b97104
--- /dev/null
+++ b/examples/docker-compose.yml
@@ -0,0 +1,10 @@
+version: '2'
+
+services:
+    redis:
+        image: squeakywheel/redis:edge
+        network_mode: "host"
+        ports:
+            - 6273:6273
+        environment:
+            - REDIS_PASSWORD=mypassword
diff --git a/examples/microk8s-deployments.yml b/examples/microk8s-deployments.yml
 new file mode 100644
index 0000000..1e481eb
--- /dev/null
+++ b/examples/microk8s-deployments.yml
@@ -0,0 +1,48 @@
+---
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: redis-deployment
+spec:
+  replicas: 1
+  selector:
+    matchLabels:
+      app: redis
+  template:
+    metadata:
+      labels:
+        app: redis
+    spec:
+      containers:
+      - name: redis
+        image: squeakywheel/redis:edge
+        volumeMounts:
+        - name: redis-config-volume
+          mountPath: /etc/redis/redis.conf
+          subPath: redis.conf
+        ports:
+        - containerPort: 6379
+          name: redis
+          protocol: TCP
+      volumes:
+        - name: redis-config-volume
+          configMap:
+            name: redis-config
+            items:
+            - key: redis
+              path: redis.conf
+---
+apiVersion: v1
+kind: Service
+metadata:
+  name: redis-service
+spec:
+  type: NodePort
+  selector:
+    app: redis
+  ports:
+  - protocol: TCP
+    port: 6379
+    targetPort: 6379
+    nodePort: 30073
+    name: redis