Code review comment for lp:~mpontillo/maas/beaconing-multicast-helper

Lee, to address your comments:

(1) I think the reason we are using /bin/sh in the scripts/ directory is because these scripts are often called using 'sudo'. Since 'sh' has more limited functionality compared to 'bash', we decided that intentionally. (in order to reduce the attack surface) I would actually have preferred to use bash, since the sh-isms in this script are a bit annoying. ;-)

(2) The script works on a best-effort basis. Not all interfaces will be able to join multicast groups, so forcing a failure isn't really helpful. Lack of success is helpful to know about, which is why a message is printed for each confirmed-successful join or leave.