[SRU] zfs-linux should be using python3 for python userspace tools

As we discussed, this should just be a matter of changing the package dependency. The actual scripts support Python 3.

This assumes that the python3 package is using the alternatives system such that /usr/bin/python will still exist on a python3-only system.

Elevating priority to "critical", as this is blocking zfs from landing in the default Ubuntu Server seed. Adding a task for Xenial, and marking this bug for SRU, as we want to bring this back to 16.04 as well. Thanks!

This bug was fixed in the package zfs-linux - 0.6.5.8-0ubuntu2

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zfs-linux (0.6.5.8-0ubuntu2) yakkety; urgency=medium

  * Use python3 for arcstat.py, arc_summary.py & dbufstat.py (LP: #1627909)
    - update dependency to python3 and set paths to use python3

 -- Colin Ian King <email address hidden> Mon, 26 Sep 2016 18:49:12 -0500

Hello Colin, or anyone else affected,

Accepted zfs-linux into xenial-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/zfs-linux/0.6.5.6-0ubuntu13 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-needed to verification-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

I tested 0.6.5.6-0ubuntu13 on a Xenial system with no python2 installed; only python3. I did this by first upgrading the ZFS packages and then purging the python2 packages. All three scripts work as expected. I did a basic run of each with no arguments.

For the record, in case anyone has this same concern... I'm not in love with patching the scripts to use /usr/bin/python3, but that does seem to be necessary. When I removed python2, there is no /usr/bin/python. I had expected that the python3 package would use the alternatives mechanism to register /usr/bin/python, but that does not seem to be the case.

Accordingly, I have marked this verification-done.

Tested here, works for me too.

Colin, Andy, thank you!

This bug was fixed in the package zfs-linux - 0.6.5.6-0ubuntu13

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zfs-linux (0.6.5.6-0ubuntu13) xenial; urgency=medium

  * Use python3 for arcstat.py, arc_summary.py & dbufstat.py (LP: #1627909)
    - update dependency to python3 and set paths to use python3

 -- Colin Ian King <email address hidden> Tue, 26 Sep 2016 07:35:44 -0500

The verification of the Stable Release Update for zfs-linux has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.