If you are running a 2.4.5 install you will notice that there are still a few bugs (most of which have been patched at this point).

The patches that I recommend for any 2.4.5 Zenoss users are the following.

Patch 15003 - Corrects the following bug: http://dev.zenoss.org/trac/ticket/5494

Patch 14397 - Adds the following feature: http://dev.zenoss.org/trac/ticket/5375

Patch 15214 - Corrects the following bug: http://dev.zenoss.org/trac/ticket/5473

(this patch only partially corrects the issue, read the comments on the Trac page for details)

Patch 14049 - Adds support for the use of "dmd" in transforms (as you would use it in zendmd).

Patch 13304 - Corrects the following bug: http://dev.zenoss.com/trac/ticket/4914

Patch 16733 - Corrects the following bug: http://dev.zenoss.org/trac/ticket/5978

These patches can be applied with the following command (run as the zenoss user):

zenpatch 15003 && zenpatch 14397 && zenpatch 15214 && zenpatch 14049 && zenpatch 13304 && zenpatch 16733

Restart Zenoss after applying the patches.

Also, if you are using the WMI Data Source ZenPack you will want to install version 1.5 of the ZenPack before upgrading: docs/DOC-3392.  If you upgrade to Zenoss 2.5 without upgrading to version 1.5 of the WMI Data Source ZenPack you will break your Zenoss install.