On 10/28/2013 10:49 PM, Lorenzo Colitti wrote:
On Tue, Oct 29, 2013 at 6:53 AM, Phil Mayers <p.may...@imperial.ac.uk <mailto:p.may...@imperial.ac.uk>> wrote:I wanted to follow up on this. Some folks from Cisco kindly contacted me off-list, and correctly guessed that a large number of the IPv6 neighbour entries were in state "STALE", and pointed me to the relatively new: ipv6 nd cache expire <seconds> ...interface-level command. This wasn't in the IOS train we were running until relatively recently, so I hadn't seen it before. I wonder what the designers were thinking when they did the original implementation. Without this option, a box with enough client churn could run out of neighbour cache entries even if all the clients are perfectly behaved. Perhaps they didn't think of it because it doesn't happen in IPv4 due to a) much fewer addresses on a given box due to scarcity and b) ARP has timeouts.
Probably not scarcity in 1918 world, but I think you hit the nail on the head with "arp has timeouts." :)
Doug
