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JUNOS High Availability by Orin Blomberg, Senad Palislamovic, Kieran Milne, James Sonderegger

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Post-Upgrade Verification

Post-upgrade verification should begin at the Physical layer on the device that has been upgraded, and expand upward through the Open Systems Interconnection (OSI) model and outward through the rest of the network. However, before beginning this process, we recommend confirming that the chassis is currently running on the desired (upgraded) revision of JUNOS.

On more than one occasion, we have been surprised to find a chassis that did not get fully upgraded. Either a hardware or configuration incompatibility occurred that we had overlooked, or we simply failed to reboot the RE to allow it to come up on the new software.

Take a look at the revision of JUNOS the master RE is currently running and make sure it matches the target release:

lab@j2300-1-re0> show version
version 9.3R3.8;

A commonly overlooked but critical next step is to confirm that the upgrade was also successful on the backup RE. Checking the backup software version is important because a chassis is not really in a fully redundant high availability state unless the backup components (in this case, an RE) are capable of performing the same tasks and supporting the same functionality as the primary components.

Log in to the backup RE and check its release:

[edit]
lab@m40-3-re0# run request routing-engine login re1

lab@m40-3-re1> show version
version 9.3R3.8;

You can also check the JUNOS revision level from configuration mode, but it is important to keep in mind that what you are viewing in configuration ...

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