Clarification on simple, incremental ZFS backup

Brandon J. Wandersee brandon.wandersee at
Wed Jul 1 14:13:21 UTC 2015

Hey, folks. So a month or so ago I installed a shiny new root-on-ZFS
system on my laptop. For some time I've been keeping incremental backups
on an external USB drive using sysutils/rsnapshot, a front-end to rsync,
but I've been interested in implementing the same sort of functionality
using ZFS snapshots. I've read the relevant sections of the Handbook and
looked around the web a bit, and the typical procedure recommended is
that I simply replicate the filesystem:

  `zfs send -R <source_pool>@<snapshot> | zfs receive <backup_pool/backup_fs>`

There's a problem with this, though: when the filesystem is replicated
all its properties are retained (naturally), including mountpoints. So
the backup gets mounted over my local filesystem, making both
useless. There's no way that I can see to unmount the backup filesystem
(as that's now mounted to '/'), and importing the filesystem again after
a reboot just mounts it over the local filesystem again. What am I doing
wrong, here? Can anyone point me in the right direction? Does anyone
here have a similar rsync-like backup scheme?

   		      :: Brandon Wandersee ::
                  :: brandon.wandersee at ::
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