PIX 515E "Memory Usage" always maxed out

[dbryden68]

We have a PIX 515E runing version 6.3(3) that has 64 Megs of RAM installed. We are primarily passing mail on port 25 and UDP DNS queries through this firewall. We average aout 8kbps in/out but at heavy traffic times will see about 14kbps of traffic in/out.

I have noticed that the RAM on this firewall is alway running around 62 meg used out of the 64. If I reload the firewall the ram stays low for about 24 hours and then climbs and never comes back down. I don't know if there is a bug in this firewall or whether I have reached some kind of limit on it.

Any advice would be greatly appreciated. I don't even know where to start.

[dbryden68]

I forgot to mention that I am not seeing any noticable problems. The firewall is not reloading on its own or denying any traffic that I can tell.

[erickflamenco]

Begin looking for warning messages on the syslog server, you should enable logging to a server, then you'll have a more clear idea of what's consuming the memory resources.

[erickflamenco]

While in troubleshooting mode, you must set logging to level 7.

Erick

[thomam04]

Hello,

I suspect you run into bug: CSCec45748 ( New DNS conns reset the idle timer of previous DNS conns.) Please verify how many connections you have and what they are. Do a "sh conn detail". If most of your connections are DNS/UDP I would recommended to upgrade to PIX OS 6.3(4).

-Markus