I have an SRX100 that I am trying to boot form the backup partition/slice. I do NOT have this CLI command available:
request system reboot slice alternate media internal
I have tried setting boot.current to 'alternate' and 'backup' using uboot and the loader but ths has not had an affect. My searches have not shown anything beyond changing that variable, which doesn't seem to work. Is there any reference out there on how to do this?
It is not possible to boot Junos from backup partition.
The backup partition is a recovery partition. So, if the primary root partition becomes corrupted, the system can still boot from the backup Junos OS image located in the other root partition and remain fully functional. For more information, please refer to the following technical documentation - https://www.juniper.net/documentation/en_US/junos/topics/concept/switch-resilient-dual-root-partitions.html
May I know the reason why you would like to boot Junos from backup partition?
If the commands from loader and uboot are not working, then the only way I think you could do that is by unplugging the SRX. Upon an unexpectedly power outage, the branch SRXs usually bootup from the secondary partition because they primary partition gets corrupted. I am wondering why you are looking to bootup the SRX from the backup partition though.
Hope this helps you.
And btw, you will have to recover the primary partition later:
Thanks for the replies. I was wanting to boot up from the backup partition because I had performed a software upgrade, and though I could boot into the upgraded partition, it was not operating correctly, there were error messages sent to the console and it would hang for long periods of time. As the original software was on the backup partition I wanted to boot to that. The issue did end up getting resolved, as the new software started working properly for some reason.
Well, I'm glad everything works as expected
However, I would suggest you take a snapshot of the SRX in USB flash drive, so that if you run into an issue next time it will be easier to recover.
Now that everything is working fine you could copy the OS in the primary partition to the secondary one. This way if the SRX boots from the backup partition in the future, you wont have any problems introduced by the use of an old/different Junos OS: