Upgrade to pfsense 2.3.1 in Hyper-v 2008 R2 failed - unbootable
After upgrade to 2.3.1 pfsense canot boot with error:
Mounting from ufs:/dev/ad0s1a failed with error 19.
The name of the root partition has probably changed to ada0s1a, try entering ufs:/dev/ada0s1a at the prompt.
the right solution is here: