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New Member

IDS mem 99%

Dear All

I have IDS 4235 with 1 GIG RAM and mem are 99% i dont know what to do, the ver is 4.1


Re: IDS mem 99%

I can guarantee that the Cisco engineers are going to tell you to upgrade to 6.x. Beyond that, I would recommend you upgrade to 5.x since signature support stopped for 4.x some time ago. Odds are also that memory is being held for disk caching etc instead of being solely in use by the CIDS processes. Is it dropping packets or have you noticed performance issues?

New Member

Re: IDS mem 99%

there is dropping for packets since its IDS not IPS but regarding performace its about high mem utilization.


Re: IDS mem 99%

What was meant by "dropping packets" was the sensor actually discarding packets instead of inspecting them

You can look for this on the command line by watching a show events. The sensor will display what the percentage of "dropped packets" are occurring if at all.

What happens is the IOS stores all of the packets inbound to its sensing interface in a temporary cache and queues them up for inspection. Since the cache has a finite size if it gets to large, the sensor simply rejects new input and "gets behind" in its inspection. What you see is a resource hit of the CPU and or memory pegged at nearly 100%.

You really should upgrade to 5.x as some of the newer engines in 5.x actually directly address many of the issues you will run into in 4.x, and more importantly signature support for 4.x ended quite some time ago, so you will not be able to detect the more recent worms/exploits/etc.

Hope this helps sir!

New Member

Re: IDS mem 99%


You also have to take in consideration if he isnt logging/capturing some pkgs. That would for sure increase the memory consumption.

No doubt the Appliance has to be upgraded at least to 5.x