I once installed Check_MK into an existing Nagios installation, back then by using a plain source package. This also meant I had to take care of installing and configuring all dependencies like Apache, Nagios and PNP4Nagios. Keeping this setup working was quite tedious over the last two upgrades (1.2.4 to 1.2.6 and finally 1.2.6p16) so I decided to switch to the official Check_MK CRE packages instead. For now I switched to the rather outdated 1.2.6p16 packages to concentrate on migrating my configuration first.
What is following is a list of unsorted notes and pitfalls I ran into when porting my configuration.
cmk --restorecommand did not really like the archive taken from the old installation. OMD and non-OMD installs seem to differ quite a bit.
- The WATO snapshot restore functionality did not like the snapshot taken from the old installation either.
- Parts of the configuration were applied anyway so after trying the two restore formats both user accounts as well as hosts were present.
- Imported users were locked. Manually enabling them worked though.
- All host tags were missing. Manually copying
etc/check_mk/multisite.d/wato/hosttags.mkinto the new site (and of course fixing the file owner) fixed that.
- Make sure you install the same Check_MK plugins and plugin version in the OMD site, otherwise you may run into exceptions when trying to edit hosts or services since they refer to non-existant check types.
- It looks like
mkp installdoes not check for the Check_MK version numbers so you might accidentally install a plugin made for 1.4.0 in a 1.2.6 installation!
- All graph data was lost. It wasn’t part of the backups (understandable, since the previous pnp4nagios installation was not managed). It might work to copy data to
/omd/sites/<sitename>/var/pnp4nagios/perfdata/before starting the site and use
cmk --convert-rrdsto convert older single-file data to multiple files but I decided to simply drop history data.
/omd/sites/<sitename>/etc/nagios/nagios.d/tuning.cfgsince I use Telegram Notifications in Check_MK and that setting is needed to forward user attributes to the notification script.
Overall the migration was a bit tricky but it seems to be working fine now. Next up is upgrading to Check_MK 1.4.0 of course.