Re: notification about corrupt files from "btrfs scrub" in cron

[Duncan <1i5t5.duncan@cox.net>]

ST posted on Wed, 22 Nov 2017 21:54:10 +0200 as excerpted:

> Hello,
> 
> I have following cron job to scrub entire root filesystem (total ca.
> 7.2TB and 2.3TB of them used) once a week:
> /bin/btrfs scrub start -r / > /dev/null
> 
> Such scrubbing takes ca. 2 hours. How should I get notified that a
> corrupt file was discovered? Does this command return some error code
> back to cron so it can send an email as usual? Will cron wait 2 hours to
> get that code?
> 
> I tried that command once without "> /dev/null" but got no email
> notification about the results (eventhough the check was OK) - why?

See the btrfs-scrub manpage...

Note that normally btrfs scrub start is asynchronous and should return 
effectively immediately, the only possible errors therefore being for 
example if the given path doesn't point to a btrfs or btrfs-device (which 
would return a status code of 1, scrub couldn't be performed), etc.

Status can be checked via btrfs scrub status, and/or, or you can use the 
btrfs scrub start's -B (don't background) switch, which will cause it to 
wait until the scrub is finished and print a summary report.  That should 
allow you to check for a status code of 3, scrub found uncorrectable 
errors, as well.

-- 
Duncan - List replies preferred.   No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master."  Richard Stallman