Sorry for the late reply, I didn't get any notifications of your response. After I reported this issue there were a couple of updates to ZFS. This problem never occurred again, and there were several updates that redid initramfs, kernel, etc..., with the pool being imported and mounted. Didn't have to mark it for no cachefile either.
Looks to me this is fixed. * zfsutils-linux-0.6.5.6-0ubuntu14 * Linux erebus 4.4.0-36-generic #55-Ubuntu SMP Thu Aug 11 18:01:55 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1624844 Title: Ubuntu 16.04 breaks boot with wrong zpool.cache To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/zfs-linux/+bug/1624844/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs