Downtime and the perils of Slackware current
I woke up this morning to a mail informing me that WordPress had been upgraded to version 4.4.1. Shortly after I tried to access my blog to verify that everything had gone smoothly, but unfortunately my webserver showed no sign of life. Since I’ve previously had a few hard learned lessons with the RPi2, that made me a bit uneasy. A couple of hours later though, as I was reviewing my logs, the problem became pretty obvious:
[Thu Jan 07 04:40:39.291657 2016] [mpm_event:notice] [pid 25600:tid 1995767808] AH00494: SIGHUP received. Attempting to restart httpd: Syntax error on line 66 of /etc/httpd/httpd.conf: Cannot load lib/httpd/modules/mod_security2.so into server: /usr/lib/libcurl.so.4: undefined symbol: SSL_CTX_set_alpn_protos
In short, logrotate had done its thing and killed Apache, but the webserver could not be restarted due to an error with ModSecurity. After checking out the issue regarding ModSecurity, it became clear that it needed to be recompiled after the latest curl update.
Usually I do a restart of all essential services after applying updates to a Slackware current installation, seeing how continuous library updates eventually ends up breaking third party applications. However, since the last batch of updates took forever to install on the RPi2, I had most likely forgotten.
Conclusion: a case of sysadmin failure and not a Slackware problem.