Using the ioSafe N2 as a Backup via Cloning

2013-09-16 • SEND FEEDBACK •
Related: backup, Carbon Copy Cloner, cloning, ethernet, NAS

See also How to Safely Transfer Data or Verify Backups and also general backup strategies and how-to.

Cloning volumes as a backup strategy is highly attractive, so what about that approach with the ioSafe N2 NAS?

The idea of a fireproof and waterproof NAS that can function as a backup drive via cloning is attractive because it can be located some distance away from the computer, yielding a certain measure physical protection against theft/fireflood (by physically separating computer and backup), while also being fireproof and waterproof.

For example, one might locate the ioSafe N2 NAS in a detached garage or nearby structure (so long as one has network connectivity there from the computer).

No matter what:

One backup = BAD.
Redundant multiple backups (three or more, and not all together) = GOOD.

Limitations of cloning to a NAS

Cloning to a NAS is relatively low performance; that is a limitation of the relatively low speed and high overhead of a NAS on a gigabit ethernet link. In MPG testing of the ioSafe N2, write speed trended towards 30-40MB/sec for large files, and considerably less than that for thousands of small files; expect backups to a NAS to be poky.

Performance expectations should be set accordingly: a local copy to a USB3 or Thunderbolt drive is many times faster. Accordingly, keep multiple backups using conventional drives, but use the NAS as an additional redundant solution. One backup is unwise in all cases anyway!

Wireless network (non ethernet) connectivity suffers even more and MPG does not advise that usage for anyone except those with extraordinary patience or very small data sets. Using wired gigabit ethernet is always better than (overhyped) wireless speeds.

There are some technical limitations that restrict the type of clone backups that can be made to a NAS.

Cloning the boot volume

Cloning the boot (system) volume to a NAS is not supported; use a drive attached to the computer directly in order to create a fully bootable perfect copy of the boot volume.

It is possible to clone subfolders on the boot volume, as shown further below.

Cloning limitations for the boot volume to a NAS

Cloning folders on the boot voume

Subfolder(s) on the boot volume (or any volume) can be cloned to a NAS volume, as shown below.

As shown below, the folder Master is being cloned to the NAS volume ioTM.

One or more folder(s) can be cloned this way as files onto the NAS. One might create different destinations for this purpose, e.g., a volume on the NAS named Master-Clone to match (in this example), the source folder of Master.

Cloning a folder on the boot/system volume to a NAS volume for backup

Cloning a volume (non system volume)

Cloning a non system volume is possible; Carbon Copy Cloner does this as a sparse disk image file saved onto the NAS.

Cloning an entire volume onto a NAS for backup.

The result is a special type of folder with extension “.sparsebundle”. In this case, the volume Master was cloned to the NAS, creating the resulting folder Master.sparsebundle.

Double-clicking the Master.sparsebundle file results in a volume Master appearing on the desktop*; this is a mounted volume whose backing store is the files inside the Master.sparsebundle folder. You will not want to do this except perhaps to restore certain files (very slow over the network). But it can be used to clone back onto a local drive, e.g., to restore this backup to a local drive.

* After a lengthy delay; mounting the volume this way is very slow over the network.

The “sparsebundle” backup clone, mounted on the desktop as a volume