standby mode ARP table?

[jimmychuang]

When the firewall is in standby mode, will it still actively clear the ARP table?

[AkosBakos]

Could you clarify the question? Why do you mean about "clear the ARP table"

[jimmychuang]

If Firewall A was originally active, but the cluster switched to standby for some reason, will the old entries in Firewall A's ARP table be automatically deleted, even though it won't acquire new MAC addresses?

[PhoneBoy]

ARP tables are not synchronized between cluster members, each node manages their own per the usual rules in Linux.

[jimmychuang]

I know this, but what I want to understand is whether ARP continues to function when the firewall is in standby mode. Will the old ARP tables be automatically deleted?

[PhoneBoy]

As stated, each member manages their own ARP tables independently.
That includes purging out ARP entries that aren't used after a period of time (meaning no traffic has come from/to that particular IP).
Again, this occurs according to the standard Linux rules for this.

[JozkoMrkvicka]

Well, ARP cache entry topic is not as simple as one would think.

For much higher overview how ARP works, see THIS and THIS answers.

[JozkoMrkvicka · Accepted solution]

No, standby member will not delete ARP entries despite the fact that it should do it after timeout is reached (set arp timeout), by default 60 seconds.