[c-nsp] Datagrams (max data segment is 536 bytes)

[Oliver Boehmer (oboehmer)]

> 
> On my BGP customers peers box, i see a very small data segment :
> 
> GATEWAY#show ip bgp neighbors | include data segment
> Datagrams (max data segment is 536 bytes):
> Datagrams (max data segment is 536 bytes):
> Datagrams (max data segment is 536 bytes):
> Datagrams (max data segment is 536 bytes):
> Datagrams (max data segment is 536 bytes):
> Datagrams (max data segment is 536 bytes):
> Datagrams (max data segment is 536 bytes):
> Datagrams (max data segment is 4430 bytes):
> Datagrams (max data segment is 536 bytes):
> 
> Could that be normal, if not what could cause that ?

This is normal, by default IOS uses 536 bytes. You can (and you should)
increase this by enabling PMTUD ("ip tcp path-mtu-discovery"), but
please make sure you check the recent PSIRT advisory first
(http://www.cisco.com/warp/public/707/cisco-sa-20050412-icmp.shtml)

	oli