[squid-users] Change of server hardware (?) resulted in massive increase of crashes

[Ralf Hildebrandt]

I've been running squid-5 and squid-6 (both release and HEAD) on my
old proxy farm. Four machines, ubuntu bionic. All was well, except for
the occasional crash.

I filed bug reports, and the preliminary patches helped with the
crashes:

https://bugs.squid-cache.org/show_bug.cgi?id=5055
https://bugs.squid-cache.org/show_bug.cgi?id=5056

Recently, I set up a new cluster of four up to date machines with new
hardware (still ubuntu, focal though, still x64, assloads of CPUs and
memeory) and tested that cluster with the users from our department.
All went well, squid never once crashed.

Then we took the old cluster offline, and let the new cluster take over.

Now I'm getting (with the same hand-build squid versions!) a LOT
(about once every 15 Minutes) of crashes like this one:

2020/09/22 09:34:07| FATAL: check failed: opening()
    exception location: tunnel.cc(1305) noteDestinationsEnd
    current master transaction: master359979

My infrastructure generates backtraces upon crash, but in the case I'm
not getting any. Which is odd, given I start squid in gdb with
"/usr/sbin/squid -sYNC"

--
Ralf Hildebrandt
Charité - Universitätsmedizin Berlin
Geschäftsbereich IT | Abteilung Netzwerk

Campus Benjamin Franklin (CBF)
Haus I | 1. OG | Raum 105
Hindenburgdamm 30 | D-12203 Berlin

Tel. +49 30 450 570 155
ralf.hildebrandt at charite.de
https://www.charite.de