https://www.truenas.com/community/threads/cannot-fetch-portsnap-connection-reset-by-peer.90154/
SOLVED - Cannot fetch portsnap. Connection reset by peer | TrueNAS Community
I just upgraded (a friends) FreeNAS 11.1 to 12.0-U1, and went through a few updates to get there. I also updated all jail (iocage) to 11.4 before upgrading...
connection resetsolvedcannotfetchportsnap