We might receive below error in a standalone or VC setup while performing software rollback
user> request system software rollback all-members
fpc0:
--------------------------------------------------------------------------
ERROR: Cannot rollback, JUNOS image in alternate root is not valid
fpc1:
Junos version '19.4R3-S7.3' will become active at next reboot
fpc2:
fpc3:
fpc4:
fpc5:
Backup partition on FPC 0 could be corrupted
user> request system snapshot slice alternate member 0
Formatting alternate root (/dev/da0s2a)...
Copying '/dev/da0s1a' to '/dev/da0s2a' .. (this may take a few minutes)
The following filesystems were archived: /
Once it is completed, please verify the partition status. Now we could see both primary & backup partitions. Further, we were able to roll back the software without any issues as expected.
user> show system snapshot media internal member 0
Information for snapshot on internal (/dev/da0s1a) (primary)
Creation date: Apr 23 14:29:53 2022
JUNOS version on snapshot:
jcrypto-ex: 19.4R3-S7.3
jdocs-ex: 19.4R3-S7.3
jphone-home: 19.4R3-S7.3
jsd : powerpc-19.4R3-S7.3-jet-1
jsdn-powerpc: 19.4R3-S7.3
junos : ex-19.4R3-S7.3
junos-ex-4300: 19.4R3-S7.3
jweb-ex: 19.4R3-S7.3
Information for snapshot on internal (/dev/da0s2a) (backup)
Creation date: Jul 25 09:53:28 2023