I wasn't running at 100 % until this afternoon. I use intermapper and I wasn't having any issues until today becuase it lets me know when I hit 90 % use. Every so often it hits 100 % and I'm not sure how to find out what is causing it. The amount of bandwidth varies but is usely around 1 to 2 mgbs. Please advise.

Check the connection number in
If you have a lot of connections (more than 2000) probably the problem is this.
In this case you must limit connections using firewall rules.
Can you specify your hardware?

It is a rb532 with duaghter board 564 on it. It is connected to a 768k up and 7.1 mgbs down dsl line. I have all connections limited to 40 or 50 per ip because I have 5 different ip ranges routed through this unit. This has had the same configuration for months.

also you can check pps (packets per second) that number can be very big even with low bandwidth and seriously put strain on the router.

5:28 am was the last time it was under high cpu usage and it is currently 7:48 am now which is strange becuase it had been hitting over 90% every 15 to 45 minutes all night long. The only thing that has happened was at 6:00 am when it sent a backup email to me.

what do you consider to be a lot of packets per second. I've been watching and the max that I have seen was around 280 pps.

ive seen 100% load because of corrupted winbox saved sessions. if you close all instances of winbox, and use ssh to login, do you still see 100% cpu?

/system resources print

Sam

No one was logged in at all when this was happening and so far it hasn't happened since 5:30 this morning. My intermapper was showing high cpu usage and I would lose connection to routerboard during the times I was actually trying to see what was going on. I figured it was a prolem with too many connections but I haven't found this to be true. I wish I knew what caused it but then again it wouldn't make me mad if it never done this again. If I see it start back up I post again but until then thanks for trying.