Cacti has proven to be a pretty useful tool in my experience, but recently, one of my installations seemed to be plagued with random graph drop outs.
I’d not seen this sort of issue before that wasn’t related to network issues, but Smokeping, and other network tests didn’t show any issues with connectivity. Additionally, the Cacti poller logs didn’t seem to indicate any errors, but would say that the polling run had completed, and polled X number of hosts, but X was fewer than the total.
Unfortunately, it didn’t seem that my google fu was strong in this instance, or other people haven’t run into this much, so I hadn’t been able to find much in terms of causes or solutions. Which, as everyone knows, leaves the only remaining course of random guessing.
So, I decided to try using the Spine poller, rather than the default PHP one. This required (in ubuntu) installing the cacti-spine package, configuring the /etc/cacti/spine.conf file with the proper database details, and choosing the Spine poller in the Cacti admin interface.
Which as you can see magically fixed my Cacti graphs. I’m still not sure why the default poller was neglecting to poll certain hosts intermittently, but even if the default poller is working well, the Spine poller is a LARGE amount faster, so it’s certainly recommended, especially if you have larger numbers of hosts.