Plusnet Sagemcom 2704N ARP Cache

[#1]

Does anyone know how long it takes for ARP cache entries to expire? Or if there is any way to trigger a refresh? (I have tried a reboot).

A raspberry pi with a static IP took the address of my NAS from DHCP before I finished setting everything up, and now the ARP table has the Pi's mac address under both IPs.

[#2]

It's the ARP cache in your router (which provides the DHCP functionality) that you need to refresh.

A reboot of your router would clear the cache & issue fresh DHCP / IP connections.

[#3]

I tried that but it didn't do anything - I have turned off DHCP as my Raspberry Pi does that for my network, maybe it needed to be on.

I left it overnight, plugged the NAS back in and it seems to have resolved itself.