Could an update rename my boot pool?

[slamilton]

This morning I noticed I was missing a pool I previously had ("dot_system") and now have a new pool I've never seen before ("freenas-boot"). I'm trying to figure out what happened and if this is an early warning of USB failures. This was concerning as "dot_system" was my boot pool and now "freenas-boot" is the boot pool.

Timeline

• ~2 weeks ago - I updated from 11.1-U5 to 11.2-U7
• Last night - Likely first scrub of "dot_system" since this update
• This morning
  • Got alert "dot_system" was "ONLINE: One or more devices are faulted in response to IO failures". Attempting to SSH resulted in an infinite connection hang (although authentication succeeded, it was allocating the TTY that never happened). WebUI appeared to be unreachable.
  • I used management system to power cycle the box, and it boots successfully.
  • WebUI shows "dot_system" is now "UNKNOWN". zpool status status shows no entry for "dot_system", but I have a new entry "freenas-boot" shown as ONLINE with no errors. It appears to be using the same partition that was previously used for dot_system. Tried to import "freenas-boot" in the WebUI and it is not showing up

Can anyone help me figure out what happened?