DHCP clients lose IP addressing

[davesc63]

Hi all,

Opnsense running dhcpv4 service with default lease times
LAN and WAN connected to a simple unmanaged switch
Eero 6 connected to the same switch

When I take opnsense offline, my dhcp clients release their IPs within a minute of opnsense going offline. Am I missing something fundamental here? I always thought clients would hold on to their IPs for the lifetime of the lease and at the half-time point would seek to renew their lease.

It's only an issue when I'm doing maintenance activities recently (upgrades for software / hardware / tweaking). I would have thought my LAN clients would:
A) hold their leases
B) still be able to communicate on the LAN

As the clients are on the LAN, flat /24 home network, connected to the same switch, that communication would still work. LAN comms should not have to go via opnsense

It almost feels like when opnsense goes offline, a release broadcast is sent. I notice all my dhcp clients change to apipa (169.254.x.x) addressing very quickly after opnsense is offline

How can I resolve this?
I just want clients to hold their lease and still communicate locally when opnsense is offline

Example of why this is an issue:
Opnsense offline, my local machine loses IP and changes to apipa, I then can't access admin UIs such as proxmox / Home Assistant which have no reliance on routing through opnsense. I can manually set my IP and gain access but I would prefer to keep all clients as dhcp

Thank you

[Monviech (Cedrik)]

Default lease time (seconds): 86000
Maximum lease time (seconds): 86400

Leases are then valid for 1 day.