Cisco Routers Loses "Running-Config"

[Paki]

Hi Dear

Hope this email find you in best of health.

Main Problem: My router's "running-config" lost after reload.

I do "copy run start", "wr" & "wr memory" but even-then the problem exists.

The main problem is router's flash with Cisco 3725 & 7200 series routers.

Moreover, my routers memory get fill so early that I can not even save my running-config over there. Sometime I get "exec" memory full & sometime "flash". Since running-config are save in NVRAM, can I increase my router's NVRAM etc.

What is disk0 all about? & what is the maximum value for router flash, NVRAM etc.

Your early response will be highly appreciated.

Thank you for your valuable time

[Richard Burts]

It looks like you have at least two issues going on. If the router boots and does not use the startup config which you had saved then that is not related to flash getting full. The most common cause of not using the startup config is that the config register has been set to 0x2142. Check the current value of your config register using the show version command. Look toward the bottom of the output and it will display the current setting of the config register. If it is 0x2142 then set it to 0x2102.

If the config register is correct then the next step would be to verify if copy run start is working. Make a config change. Then do copy run start. Then use the show startup command and look to see if your change is in the startup config.

HTH

Rick

[Paki]

Dear Richard!!! My configuration register is 0x2102.

As per your advise, I altered my configs & then saved it but again got the same results.

I am really getting fed-up of this issue.

[Richard Burts · Accepted solution]

Thanks for confirming that your config register is 0x2102. This is one potential problem that is eliminated. I would like to see the entire booting process. For this you would need to establish a session to the console port of the router, make sure that logging to the console is enabled, boot, and copy and paste all of the messages generated during the boot process.

HTH

Rick

[Joseph W. Doherty]

Rick has addressed you're boot issue, but as to running out of flash space, first determine if there's anything on the config's flash you don't need, and delete it.

BTW, the older Cisco flash format, when files were deleted, didn't release the storage space, you had to run a separate compress command to reclaim the deleted storage space.  The later IOS versions support a flash format that will automatically reclaim deleted file space, but if your flash is still using the older format, you need to reformat the flash to obtain its benefits.  (NB: of course, reformatting a flash will wipe all current flash contents.)

Also BTW, system crashes will write crash dumps to flash, and I've seen cases where those files will consume all your free flash space.

If you have a very large configuration, there's often an option, which you may want to look at, where you can enable the configuration be saved in a compressed image.

To your question about increasing the size of flash, or using disk0, flash options vary per platform, including what options you have for increasing or adding flash.  Depending on a device, something like disk0 might be an alias for on-board flash, or it might be the name for an external flash socket (the latter often using CF).  I don't recall what the flash options are on a 3725 and for a 7200, much will also depend on what NPE/NSE is installed.

[Paki]

Joseph Dear!!! How can I solve boot issue? I am also sure that this would be a boot issue.

I have solved the flash issue. Now only my "config lost issue at startup" is remaining.