'show run' on causes 7200 to lock up

Hi,

We have 7200 routers being used for DSL aggregation. We terminate about 4000 subs on each using RBE, so the configs are quite large. When we do a 'show run' the routers basically freeze up for several minutes until the config is shown. Is this normal? My presumption is that it is because of the extreme size of our configs, but maybe there is something I can do to allow 'show config' to work without locking up the router for several minutes?

Thanks for any help.

Todd

Reply to
txqzr4
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txqzr4 a écrit :

Is it better if you add "parser config cache interface" in config mode?

Hope this helps.

Reply to
Christophe Fillot

Thanks for the suggestion. I found a command "parser cache" which I ran, but I don't see much of an improvement. I guess my big issue is that when I issue a 'show run' the whole router basically freezes up and stops passing traffic for the most part. I wouldn't mind the wait if it didn't interrupt service for 4,000 users.

Reply to
txqzr4

Open a case with the Cisco TAC

Reply to
Merv

Is the CPU highly loaded? What kind of NPE is in the boxes?

I've only seen that when the box was running way beyond what the CPU should be doing.

Reply to
Doug McIntyre

I have never dealt with huge configs so I have not seen that.

Post sh proc cpu during and not during the sh run.

sh buff might be worth seeing too.

It is possible to adjust the CPU scheduling with the scheduler allocate and scheduler interval commands.

Reduce the time spent on any task and .do something sensible with the other one.

Also post your scheduler configuration if not default

sh run | inc scheduler

If you are really loading up the router maybe you can keep a copy of the config off line (tftp, ftp, whatever) and only refer to the on-line one when you must.

You are not doing this on the console are you? Telnet would be better for sure.

Possibly you are forcing your traffic to be process switched. If so changing to the fast path may allow user traffic to be switched in interrupt mode and of the sh run to be scheduled. Not all traffic can be switched in the fast path.

Reply to
Bod43

I am doing this via telnet, our routers typically run at below 50% CPU usage with NPE-200s. I will have to see if I can do a 'sh proc cpu' from the console as I cannot re-telnet in once I have issued 'sh run'.

Reply to
txqzr4

Yes, I do that, but the problem is when I need to refer the actual online one. Mostly when I am testing things and want to re-verify what I've done.

Reply to
txqzr4

Well I found some Cisco documentation that seems to support the view that this is normal behavior when running 'show' commands with a lot output. Bummer, its annoying.

Reply to
txqzr4

It's certainly not "normal" that customer traffic is dropped when doing sh commands.

You can do sh run and sh proc cpu at the same time if you use 2 telnet sessions.

High CPU may be normal but as mentioned is it usually the case that traffic has a higher priority than housekeeping. Process switched vs fast switched.

Some services though (and it is not unlikely that yours is in this category) must be process switched,

If you post the info then someone may be able to assist,

I could add

sh int switching sh int stat

or is it sh int statistics?

Obviously NPE 200 is quite old. Things have moved on.

Reply to
Bod43

Greetings,

... snip ...

... snip ...

Is this a 7200 or 7200 VXR? While not in your type of environment, our old 7200's with NPE200 and NPE225 used to run at around 50% CPU with larger configurations, but when certain events happened they would max out and we found that 7200 VXR's performed much better under the same sort of conditions.

Cheers....................pk.

Reply to
Peter

NPE-200 with 4000 interface running 50% utilization? With 4000 interfaces how long does it take for it to come up after a reboot? If you have a VXR you can get an NPE-400 used real cheap. Your CPU should come down to less than 10% and you probably won't have the same issues with the show run command.

Reply to
Thrill5

~ > > >> > We have 7200 routers being used for DSL aggregation. We terminate ~ > > >> > about 4000 subs on each using RBE, so the configs are quite large. ~ > > >> > When we do a 'show run' the routers basically freeze up for several ~ > > >> > minutes until the config is shown. Is this normal? My presumption is ~ > > >> > that it is because of the extreme size of our configs, but maybe there ~ > > >> > is something I can do to allow 'show config' to work without locking ~ > > >> > up the router for several minutes?

~ Well I found some Cisco documentation that seems to support the view ~ that this is normal behavior when running 'show' commands with a lot ~ output. Bummer, its annoying.

Does "process-max-time 20" help any?

Aaron

P.S. "show config" will execute a heck of a lot faster

Reply to
Aaron Leonard

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