rsyslog-pgsql hangs after backgrounding

[Alexis Mousset]

If rsyslog is configured to forward logs into PostgreSQL with ompgsl, when restarting rsyslog with "restart rsyslog" and producing logs, rsyslog hangs until being restarted. Then it processes some logs, but the problem quickly happens again.

This issue has been fixed in rsyslog 7.4.10. The changelog says:
* If rsyslog was set to auto-background itself (default code behaviour, but many distros now turn it off for good reason), ompgsql could not properly connect. This could even lead to a segfault. The core reason was that a PG session handle was kept open over a fork, something that is explicitely forbidden in the PG API. (http://www.rsyslog.com/changelog-for-7-4-10-v7-stable/)

The patch (https://github.com/rsyslog/rsyslog/commit/ff091b7ea963b63130cfb77af57f137e632bf765) works fine with 7.4.4.

The problem does not happen on 15.04 as backgrounding is disabled.

Information:

# lsb_release -rd
Description: Ubuntu 14.04.2 LTS
Release: 14.04

# apt-cache policy rsyslog-pgsql
rsyslog-pgsql:
  Installed: 7.4.4-1ubuntu2.6

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.