set interfaces bridge br0 enable-vlan
set interfaces bridge br0 member interface eth1 allowed-vlan '3'
set interfaces bridge br0 member interface eth1 allowed-vlan '4'
set interfaces bridge br0 vif 3 address '10.3.0.4/16'
set interfaces bridge br0 vif 3 description 'guest network'
set interfaces bridge br0 vif 4 address '10.1.0.4/16'
set service dhcp-server high-availability name 'ha'
set service dhcp-server high-availability remote '10.1.0.3'
set service dhcp-server high-availability source-address '10.1.0.4'
set service dhcp-server high-availability status 'secondary'
set service dhcp-server listen-address '10.3.0.4'
set service dhcp-server shared-network-name 3_guest authoritative
set service dhcp-server shared-network-name 3_guest description 'guest'
set service dhcp-server shared-network-name 3_guest name-server '192.0.2.1'
set service dhcp-server shared-network-name 3_guest name-server '192.0.2.2'
set service dhcp-server shared-network-name 3_guest subnet 10.3.0.0/16 default-router '10.3.0.1'
set service dhcp-server shared-network-name 3_guest subnet 10.3.0.0/16 enable-failover
set service dhcp-server shared-network-name 3_guest subnet 10.3.0.0/16 range 1 start '10.3.10.1'
set service dhcp-server shared-network-name 3_guest subnet 10.3.0.0/16 range 1 stop '10.3.200.254'

vyos@r15# cat /config/dhcpd.leases
# The format of this file is documented in the dhcpd.leases(5) manual page.
# This lease file was written by isc-dhcp-4.4.3-P1

# authoring-byte-order entry is generated, DO NOT DELETE
authoring-byte-order little-endian;


failover peer "ha" state {
  my state normal at 5 2024/11/01 08:43:12;
  partner state normal at 5 2024/11/01 08:43:12;
  mclt 1800;
}

lease 10.3.141.37 {
  tstp 2 2024/04/23 06:39:28;
  tsfp 2 2024/04/23 06:39:28;
  atsfp 2 2024/04/23 06:39:28;
  cltt 1 2024/04/22 06:39:28;
  binding state free;
  hardware ethernet xx:xx:xx:0b:09:d5;
  uid "\001<\246\366\013\011\325";
  set shared-networkname = "3_guest";
}

vyos@r15# run show dhcp server leases 
Traceback (most recent call last):
  File "/usr/libexec/vyos/op_mode/dhcp.py", line 438, in <module>
    res = vyos.opmode.run(sys.modules[__name__])
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/vyos/opmode.py", line 263, in run
    res = func(**args)
          ^^^^^^^^^^^^
  File "/usr/libexec/vyos/op_mode/dhcp.py", line 265, in _wrapper
    return func(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^
  File "/usr/libexec/vyos/op_mode/dhcp.py", line 318, in show_server_leases
    lease_data = _get_raw_server_leases(family=family, pool=pool, sorted=sorted, state=state, origin=origin)
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/libexec/vyos/op_mode/dhcp.py", line 104, in _get_raw_server_leases
    data_lease['start'] = lease.start.timestamp()
                          ^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'timestamp'
[edit]
vyos@r15#