CARP, 1% CPU Usage, Web Interface Very Slow
I have many ALIX/WRAP boards running pfSense 2.0.2 with 2GB compact flash cards, 500 MHz AMD Geode LX800 CPU and 256MB DDR RAM. Recently I set two up using CARP and virtual IPs. These two aren't live yet, they are in the workshop, and only have between 0%~1% CPU usage yet the web interface is very slow on them.
Could this be related to the CARP set up some how? What will often happen when I am browsing the web interface is that I click a menu link to goto the "Services" page for example and it just seems to load for ever. The page never loads, but my browsing is always "loading". If I click the link again the page will load in a second or two.
It's like that first request wasn't fulfilled by pfSense in a certain time and was dropped, so my browser is left loading nothing. My other identical pfSense boxes don't do this.
It could be an IP conflict of some kind, or other interface/IP misconfiguration. It's definitely not an issue on a standard/normal setup. We do CARP clusters on ALIX all the time, and Netgate even sells a 1U unit with two ALIX boards built-in specifically aimed at a CARP design.
I have a couple of units running CARP. What I did find was that if everything for CARP was not setup properly then the interface was slow. I noticed this mostly while setting them up since I had to duplicate some settings on the secondary before CARP would work properly. Once everything was working properly them got a lot faster.
I have fixed my weird web interface time outs now. It seems just one was being particularly slow, the BACKUP CARP device, the MASTER was OK.
I took the compact flash card out of the BACKUP ALIX board and put it in a third board of the exact same spec, still slow. I then wiped and re-flashed the card, placed it back into it's original BACKUP ALIX board, and restored the config from which I had backed up to my laptop. Now its as fast as the MASTER and everything is fine, so perhaps it was a bad flash.
That may seem a bit obvious, and a waist of time posting here, but we have 40+ ALIX & WRAP boards, this has happened before.
Hopefully that will help someone else!