Idea to try - it works for HA standalone and "technically work" for HA (MNHA) in A/A for A/B or run VRRP to provide a single next hop... - if your also doing MNHA you might need to mark the route down ( conditional routing) if your BGP peering from the setup also..
Add unique server-identifier 192.168.4.2 ( primary) and .3 backup, your need to boxes to be in HA Active/active on the LAN side so they respond to dhcp... maybe think about VRRP also?
set access address-assignment pool junosDHCPPool4 family inet network 192.168.5.0/24
set access address-assignment pool junosDHCPPool4 family inet range junosRange low 192.168.5.50
set access address-assignment pool junosDHCPPool4 family inet range junosRange high 192.168.5.250
set access address-assignment pool junosDHCPPool4 family inet dhcp-attributes server-identifier 192.168.5.2
set access address-assignment pool junosDHCPPool4 family inet dhcp-attributes name-server 192.168.3.20
set access address-assignment pool junosDHCPPool4 family inet dhcp-attributes name-server 192.168.40.20
set access address-assignment pool junosDHCPPool4 family inet dhcp-attributes name-server 8.8.8.8
set access address-assignment pool junosDHCPPool4 family inet dhcp-attributes router 192.168.5.1
set access address-assignment pool junosDHCPPool4 family inet network 192.168.5.0/24
set access address-assignment pool junosDHCPPool4 family inet range junosRange low 192.168.5.50
set access address-assignment pool junosDHCPPool4 family inet range junosRange high 192.168.5.250
set access address-assignment pool junosDHCPPool4 family inet dhcp-attributes server-identifier 192.168.5.3
set access address-assignment pool junosDHCPPool4 family inet dhcp-attributes name-server 192.168.3.20
set access address-assignment pool junosDHCPPool4 family inet dhcp-attributes name-server 192.168.40.20
set access address-assignment pool junosDHCPPool4 family inet dhcp-attributes name-server 8.8.8.8
set access address-assignment pool junosDHCPPool4 family inet dhcp-attributes router 192.168.5.1
Original Message:
Sent: 2/10/2026 3:15:00 AM
From: HRISTO PETROV
Subject: RE: SRX1600 active/active MNHA cluster does not automatically synchronize DHCP lease tables between the nodes
Hi Jasper,
It is unfortunate that DHCP lease is not synced in MNHA... I would try dedicating two different ranges from the same subnet each on each MNHA node only. In this way each node will lease unique addresses.
e.g.
SRX1:
[edit access]
address-assignment {
pool srx1 {
family inet {
network 192.168.1.0/24;
range srx1 {
low 192.168.1.4;
high 192.168.1.127;
}
}
}
}
SRX2:
[edit access]
address-assignment {
pool srx2 {
family inet {
network 192.168.1.0/24;
range srx2 {
low 192.168.1.128;
high 192.168.1.254;
}
}
}
}
------------------------------
HRISTO PETROV
------------------------------
Original Message:
Sent: 12-10-2025 04:25
From: Jasper Polder
Subject: SRX1600 active/active MNHA cluster does not automatically synchronize DHCP lease tables between the nodes
Hi Community,
We are running two Juniper SRX1600 devices in an active MNHA cluster. The MNHA link is up and the DHCP configuration is placed inside the MNHA group, so both nodes share the same settings.
However, we are seeing that both SRX units are issuing DHCP addresses independently, resulting in duplicate IP assignments within the same subnet. It appears that although the configuration is synchronized, the DHCP lease tables are not shared between the nodes.
Has anyone run into this before?
Is DHCP lease synchronization supported in an active MNHA setup, or is this expected behavior?
And what is the recommended approach to avoid duplicate DHCP addresses in this type of cluster?
Any guidance or best practices would be appreciated.
------------------------------
JASPER POLDER
------------------------------