I have a Brocade FastIron FESX648 and I'm attempting to increase the ARP cache timeout on a port that is connected to an IXP. According to the Brocade docs, I can increase the timeout up to 4 hours with the setting
ip arp-age 240.
I've tried applying this setting globally, specifically to the IXP-facing port and variety of other combinations (lower and higher timeout values), but nothing seems to work. Whenever I run
show arp I can see that the ARP entries for IXP hosts are continually refreshed and never age higher than 4 minutes.
Has anyone faced a similar problem with Brocade FastIron gear and have any config suggestions or possible workarounds?