Frequent next-hop changes in the network for a large number of routes can lead to high heap utilization on the Compact Forwarding Engine Board (CFEB). This article describes how to check route flaps/network changes.
How to troubleshoot high heap utilization on CFEB.
High heap utilization can be caused by simple exhaustion of the memory, such as too large of a routing table or too many route flaps/changes in the network. Frequent next-hop changes in the network for a large number of routes can lead to high heap utilization. It can also indicate a memory leak or a hardware problem on the CFEB.
Every router platform has its own scaling capacity. The peak utilization will differ platform to platform.
show route summary start shell pfe network cfeb0 show heap 0 show heap 0 accounting pc size show heap 1 show heap 1 accounting pc size show piles show nhdb zones show nhdb management all show jtree 0 memory
The next-hop statistics output of the command show nhdb management all will show the changes and deletion of routes. If the counters increase frequently, then there are frequent route flaps. Users must then identify the source of the flaps.
show nhdb management all
Next-Hop Statistics:
Type Adds Changes Deletes Failures ------------ ---------- ---------- ---------- ---------- Discard 733 0 479 0 Reject 281 0 23 0 Unicast 1322468 5398 1317253 0 Unilist 719957 0 717624 0 Indexed 0 0 0 0 Indirect 165445 1418660 162924 0 Hold 2764506 378 2764502 0