This article provides information on how to replace a node in a MNHA or Routing Engine for a high-end device. This also applies in case you zeroized one of the nodes from the MNHA

Perform the following procedure:

1) Validate Prerequisites Before Deploying the RMA Device in an MNHA Environment

Perform the following checks on the active MNHA node before adding the RMA device:

• Ensure that the RMA device has the same hardware configuration as the active MNHA node. All FPCs must be installed in the same slots and must be online. Use the following command to check hardware: show chassis hardware
• Check the Junos OS version running on the active MNHA node and upgrade/downgrade the RMA device to match it. For OS upgrade guidance, refer to SRX Getting Started - Junos Software Installation/Upgrade
• The IKE package is required to enable ICL encryption for Multinode High Availability. If the package is missing, install it using: request system software add optional://junos-ike.tgz
• Save the configuration from the active MNHA node to a file and upload it to the RMA device under /var/tmp. Use the following command to save the configuration: show configuration | save /var/tmp/configbackup.txt

2) Prepare the Isolated RMA Device

Connect only the console cable (no other cables attached) and perform the following:

• Enter configuration mode.
• Remove the existing configuration: # delete
• Load the previously saved configuration file from /var/tmp: load override /var/tmp/<filename>
• If the configuration includes AppID and/or IDP services, download and install the required databases before committing the configuration. Failure to do so will result in commit errors.
• Commit the configuration: commit and-quit

3) Connect ICL and Reboot

Connect the ICL link on the RMA device and reboot it. Rebooting is required to enable MNHA functionality.

4) Verify FPC and PIC Status

After the device reboots, verify that all FPCs and PICs are online: show chassis fpc pic-status

5) Verify MNHA Status

Once the new node comes online, it should automatically join the MNHA cluster as the Backup. Confirm that the ICL is up and the MNHA cluster is getting joined as expected.

user@srx> show chassis high-availability information

(check for "Conn State: UP" and wait for "Cold Sync Status: COMPLETE")

6) Connect Revenue Interfaces

After confirming that MNHA SRG0 is healthy, connect the revenue (traffic‑carrying) interfaces.

7) Update or Install Licenses on the RMA Device

If the RMA device has Internet access: request system license update

If updating from a license file uploaded to /var/tmp: request system license add /var/tmp/<filename>