Alert Type

PSN - Product Support Notification

Product Affected

MX:{RE-S-1800X4, RE-MX2000-1800X4} EX:{RE-S-EX9200-1800X4} SRX:{SRX5K-RE-1800X4}

Alert Description

Once the platform performs a JunOS upgrade to an upgraded FreeBSD version, (15.1 or higher), JunOS will automatically generate a recovery snapshot with the new Junos version and current configuration.​  Further JunOS upgrades, recovery snapshot needs to be done manually.

To find which platforms in which releases use Junos with upgraded FreeBSD, see   Junos kernel upgrade to FreeBSD 10+.

Risk:  The issue depends on 1) primary media failure, and 2) the router reboots after experiencing 1. The risk of primary media failure is "low".
Criticality: High - When a router has an issue with the primary boot media, without a proper recovery snapshot, the router may not be able to boot up
Recommendation:   We recommend that you perform the recovery snapshot as soon as you satisfy with the software upgrade per your policy.

NOTE: Please check TSB18028 [juniper.net] -  "request system snapshot recovery" can cause memory corruption

Solution

Junos OS automatically recovers the Junos OS volume upon reboot, if considered defective, from the recovery snapshot, along with the configuration saved in the recovery snapshot.
In other words, when the router reboot and fails to boot from the primary partition, the software resides in the GUID Partition Table (GPT) will attempt to repair the primary partition using JUNOS software stored in the recovery snapshot using the JUNOS software and the configuration saved in the snapshot.

After you have upgraded the software on the router or switch and are satisfied that the new packages are successfully installed and running or if you have replaced one of the Routing Engines and depending on customer policy, you should also issue the request system snapshot recovery command to have a newly updated recovery snapshot. Junos OS automatically recovers the Junos OS volume upon reboot, if considered defective, from the recovery snapshot, along with the configuration saved in the recovery snapshot.
See request-system-snapshot-freebsd.html . 

Recommend Action:  We recommend that we perform the recovery snapshot as soon as you satisfy with the software update according to your policy.

How to verify the current recovery snapshot version?
execute the command 'show system snapshot'   as documented in show-system-snapshot-freebsd10.html

Modification History

2021-05-05 Happy Cinco de Mayo - adding a note about the risk of running into TSB18028 [juniper.net]
2021-04-22 Happy Earth Day - Adding EX-Series, MX-Series, and SRX-Series to the list of products affected. This is to allow notification to go out (version 5.0)
2021-04-15 added certain EX and SRX RE types - EX:{RE-S-EX9200-1800X4}   SRX:{SRX5K-RE-1800X4}
2021-03-10 First publication