5520 / Arp Cache Size?

[born2bl8]

Hi all, three quick questions & a small bit of background.

(1) is there a limit on the number of entries in the ARP table?

(2) where do i find it?

(3) can I change/increase it?

as a little background :

5520 local only routing between two VLANS.

Vlan A has a device emulating 5000 plus IP devices.

Each of these talks to a single device on VLAN B

When the number of devices emulated on VLAN A approaches approx 5800(thus 5800 arp entries) communication appears to stall. Device on VLANB stops getting responses from devices on VLAN A.

This is always when the number of devices emulated and therefore the ARP cache reaches approximate(give or take a little) 5800

Any help much appreciated
thanks, born2bl8

 

[biv343]

From the product specs:

Address database size: 16 000 entries at line rate (16 000 entries without flooding)

What software are you running?

 

[born2bl8]

Hi Thanks for the reply

S/W 6.1.0.006 BN:06

F/w 6.0.06

So am i correct in assuming the arp cache should go up to 16000 before the 5520 starts to creak?

born2bl8

 

[biv343]

Per the docs, yes. I'm not sure your issue is as much a layer 2 issue as a layer 3 issue. I've personally never had a 55XX switch with 5000 devices on a single VLAN being routed to another VLAN on the same switch. Are devices on the VLAN with the 5800 macs able to talk on that same VLAN?