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New Member

Low on memory error on Cisco Router 3660

Hi Professionals,

I cannot telnet to one of my router, the error messages is Low on Memory, try again later.I can telnet the other router and ping each other. The router which I have a problem was connected to 6 serial interfaces connected via leased line and 1 E1 connected via fiber optic. I have two another E1 controller which connected to MD110. I cannot connect to the other sites due to this error. Is there anybody who experience this problem? Please advice how can access this router and how I can fix this problem.


  • Other Network Infrastructure Subjects

Re: Low on memory error on Cisco Router 3660

Well, its going to be difficult if not impossible to fix the "problem" now. If possible, you should get someone at the site with the router in question to see if they can get in via console and if they can, do some basic show memory commands for troubleshooting and save the output.

See "" for more info on troubleshooting memory problems.

You can try and avoid this problem in the future by reserving some console memory so that you can get in should memory be low. The command to do this is:

memory reserved console

Try making kbytes 256 or 384, not clear on what is a good number, but it would probably depend on how much memory you actually have. I haven't had this work on all versions of IOS.

If none of the above helps or works, you're probably going to have to reboot the router to clear the problem, but afterwards keep a close eye to try and diagnose what the actual problem is.

New Member

Re: Low on memory error on Cisco Router 3660

try setting the IOMEM size to 25, 20 and if it is not accepting 25 giving error it cannot set looking at IOS Size.

New Member

Re: Low on memory error on Cisco Router 3660


You will have to somehow decrease the load on your router, you can do that by bringing down a link or more, I know it will bring down your services for a while but I don't think there is another alternative, once the load is down, you can then telnet ur router, plz note that low on memory means severe performance degradation, add more memory to router, decrease its laod by shifting some links to another spare router, plz do check cisco documentation regards troubleshooting high load or excessive memory usage.



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