Date: Sun, 4 Oct 2009 15:11:18 +0100 From: Alex Trull <alex@trull.org> To: freebsd-rc@freebsd.org, freebsd-hackers@freebsd.org Subject: (Ab)using rcng's features to keep rc.d-style services running should they fail. Message-ID: <20091004141118.GG95662@syndicate.internationalconspiracy.org>
next in thread | raw e-mail | index | archive | help
--lZZ4ablUVnt2XgAh
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable
Hi all,
I realised that because portupgrade/portmaster don't always=20
cleanly restart processes that have died due to being=20
upgraded (mysqld, often!) that this was something I wanted=20
to fix.
However, I'd seen the daemontools and wasn't a fan - too=20
much to configure with weird directories and so forth and=20
while monit is very powerful it also takes too much effort=20
to do what could be so much simpler.
So why not just (ab)use the rcng system with a script ? the=20
functionality is all there already to do almost everything=20
needed. To check whether something is running and (if not!)=20
start it.
So this is my dirty hack so far - runs out of cron with=20
"2>/dev/null" every few minutes and mails me about attempted=20
startups as they happen :
#!/bin/sh
# start things that should be running
find /usr/local/etc/rc.d/ /etc/rc.d/ -type f | egrep -v '(newsyslog|devd|se=
ndmail)' | awk '{print $0" status| grep \"is not running\" && "$0" start"}'=
| sh
Performance is not stunning, thankfuly my cpus are quite=20
idle.
real 0m1.198s
user 0m0.610s
sys 0m0.877s
(devd, newsyslog and sendmail are left out because their=20
scripts don't behave quite right.)
Initialy I used it purely for the /usr/local/etc/rc.d but I=20
had a base ntpd die on me one evening so decided to throw in=20
/etc/rc.d/ too. This script has also caught a few other=20
failures in port-installed daemons in addition to the=20
ever-common mysqld-upgraded one.
Of course it is relatively inefficient executing all those=20
scripts on a regular basis - but it works - has anyone=20
thought of cleaner/more efficient ways of doing this and=20
getting more out of the rcng framework ? Or simpler for that=20
matter.
--
Alex
--lZZ4ablUVnt2XgAh
Content-Type: application/pgp-signature
Content-Disposition: inline
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.13 (FreeBSD)
iEYEARECAAYFAkrIrQUACgkQey4m6/eWxTTE4ACfbtGSQRXQt/C/tSigVQ4eoXYI
P4kAnA2CP6HV2kiU0YpdrgPeYTFUVUBN
=6r53
-----END PGP SIGNATURE-----
--lZZ4ablUVnt2XgAh--
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20091004141118.GG95662>