Did auto upgrade to CORE 13.U? and had failed upgrade

[BobMCT]

I've been using TrueNAS for a couple years now and itg simply just works. Also, during that time there have been some upgrades which when notified I did the auto apply and all went smoothly. However, yesterday I did the same and it never rebooted. So I forced a reboot and now my browser cannot read the NAS Web GUI. I can, however, ssh into it. Also, my data pool is still accessible on the network to my other devices/systems.
I've kind of scoured the forums here and while I found some issues with various upgrades I could not find out what/how to either revert or recovery. Would someone please either describe the steps necessary or if I have to reinstall to regain access? Fortunately I did make a backup of my configuration and my data.
Thanks for any/all who can advise?
Thanks

My NAS machine is an old HP Slimline Pavillion w/8GB RAM and three 2.5" hdd. 1 - 120GB for the boot drive and 2 - 512GB for my data pool.

 

[Samuel Tai]

Since you have CLI access, run beadm list to show your boot environments. Run beadm activate <name of previous boot environment>, and then reboot to boot back into your previous boot environment.

Once you're back in the previous boot environment, and into the UI, go to System->Boot to delete the faulty 13 boot environment and try upgrading again.

 

[BobMCT]

THANK YOU THANK YOU THANK YOU. Not only a very rapid reply but also spot on. I appreciate your reply and after doing what you stated my NAS is back function again on the prior release. Rest assured that these instructions are now archived for future reference.
Thank you agian,
Bob M