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how to know how much extra memory need to enable DCEF....

Dear all,

I am an ISP having Cisco 7507 router having VIP2-40 cards having 32Mbytes DRAM for VIP. I am trying to enable DCEF, but is getting hanged due to memory allocation failure i.e it's exceeding 32Mb. How do i know to what extra memory i should upgrade to solve the problems?

Please give me any documents/suggestions, how to effectively utilize VIP cards to it's max extent?



With best regards... Ashok ----------- Pls kindly rate if helpful or answered your question.

Re: how to know how much extra memory need to enable DCEF....

CEF/dCEF consumes memory which depends upon the size of the IP routing table. As you might know, CEF has two tables, FIB and adjacency table, both of which are stored in DRAM. In your case the memory in the VIP card is 32MB.

Do you get any error messages like, "%FIB-3-FIBDISABLE or "%FIB-3-NOMEM?

give a show ip cef summary and check the size of the FIB table. (Central FIB table)

The VIP should also have enough memory to store a local FIB table, of the same size. To find out, use "show controller vip {slot } tech" command.

If you are running full BGP routes, Cisco recommends a min of 128 MB DRAM on the VIP card.

Hope that helps!