Exploring Best Options - My Cloud Backup to External USB3.0 Drive

My Configuration
WD My Cloud 2TB
Firmware: v04.01.02-417
700 GB used
External USB: Seagate BackupPlus 3TB (USB3.0), Partitioned (GPT scheme) into one 2TB partition and one 1 TB partition
Netgear WNDR3800 (802.11abn, 1Gb wired)
Mac Backup: OFF
iTunes: OFF
I have stopped the netatalk, wdphotodbmerger and wdmcserver processes, though they did not appear to be taking CPU time (using linux top command) once the initial scan was complete.

My intent is to use the My Cloud as a repository for Acronis backups from the various Windows 7 PCs we have as well as storage for little used files (archives of old projects), older images, media server for music files that we can stream to PCs, the entertainment system, etc. I wanted the external drive to serve as a backup for the My Cloud - nothing fancy or complicated, just a safety net in case the My CLoud disk dies. In effect, I would then have important files that I work with on my PCs stored (a) on the PC (b) on the My Cloud and (c) on the BackupPlus. In the event of a disaster it is relatively easy to shut down the My Cloud and BackupPlus and evacuate.

I know the the MyCloud is not going to win any speed races, but I wanted it to be faster for backing up wired and wireless PCs than when I connected an external drive to the USB2.0 port on the Netgear WNDR3800. I got good transfer rates when I populated the MyCloud shares from my main PC over the gigabit wired connection. Acronis backups to a share on the My Cloud run at an acceptable rate, too. I get about 30-40MB/s using Windows Explorer to copy from the PC harddrive to the My Cloud drive and about half that copying (same method, same source) to the attached USB drive. I can often do a bit better if I use FreeFileSync.

My Experiments

Since the main purpose of the external BackupPlus drive connected to the USB3.0 port on the MyCloud is to back up the My Cloud drive, I want to use a method that is as fast as possible as well as relatively easy. Safepoint seems easy (schedule and forget it). So I tried some things:

  • Safepoint creation (477 GB, 823 minutes) = 9.66 MB/s
  • rsync “rsync -rRa” (21.012 GB, 363 files, 1723 seconds) = 12.19 MB/s (I used a script and the $SECONDS variable to time the command)
  • cp “cp -a”(21.012 GB, 363 files, 480 seconds) = 43.77 MB/s (same data set as rsync, same script, substituting a cp command for the rsync)
  • My Cloud Windows App (21.012 GB, 363 files, 630 seconds) = 33.35 MB/S (same data set as above, I think this initiates a “cp” command on the linux system to perform the copy - timed with a stopwatch)

This clearly illustrates there is some overhead to the rsync command compared to the cp command. A native rsync appears a bit faster (25%) than the Safepoint, but the difference could be due to the different compositions of the datasets:

  • the Safepoint copy backed up the entire disk and there are a lot of little files
  • the 21 GB dataset I used with rsync and cp has an average file size of 58 MB

I got no errors on the rsync, but I did get several “preserving permissions for … not supported” errors on the cp command.

My conclusions:

  • Safepoint is almost as fast as “rsync”, but I have read horror stories about it in these forums.
  • “rsync” is faster than Safepoint (maybe) - needs more work from me to get a decent script than can be run out of the crontab
  • “cp” is great (relatively), but I’ll need to figure out those pesky errors and will need a decent script.
  • Windows App is almost as fast as “cp”, does not throw errors and needs no script development, but it is all manual

My questions are these:

  1. Is an “rsync” script better than Safepoint - faster, more reliable? It appears that Safepoint is using rsync, so why would an rsync script that I write be any better???
  2. Can you create the initial copy with “cp” and then keep the copy and original in synch with “rsync”, or do you need to create the first copy with “rsync” in order for “rsync” to work properly after that?
  3. Any other thoughts or suggestions for a scheme to backup the main disk on the 2 TB My Cloud to the external USB3.0 disk?

Other things I am going to try

It occurs to me that the Seagate BackupPlus (which screams when connected directly to my USB3 port on my desktop PC) may not be playing well with the My Cloud for some reason. So I am going to try plugging in a 2 TB WD My Passport Ultra that I have and see if that makes any difference to the numbers.

Thanks in advance for any and all constructive suggestions and feedback!!

Hello and welcome to the community,

I have never tried rsync since it is not supported. Lets see if any other user has experience with this and can share some comments.

“rsync -rRa”

Seems you are repeating flags:

-a, --archive   archive mode; equals -rlptgo

-W, --whole-file            copy files whole (w/o delta-xfer algorithm)

-h, --human-readable        output numbers in a human-readable format

http://linux.die.net/man/1/rsync

There’s a few more flags and options.  Some ideas about compression options and using tar.  I plan on using rsync.

http://serverfault.com/questions/43014/copying-a-large-directory-tree-locally-cp-or-rsync

  1. Is an “rsync” script better than Safepoint - faster, more reliable? It appears that Safepoint is using rsync, so why would an rsync script that I write be any better???

  2. Can you create the initial copy with “cp” and then keep the copy and original in synch with “rsync”, or do you need to create the first copy with “rsync” in order for “rsync” to work properly after that?

  3. Any other thoughts or suggestions for a scheme to backup the main disk on the 2 TB My Cloud to the external USB3.0 disk?

  4. Likely the same thing but with different options than what you used.  I don’t trust automatic backups but if you match the flags, it shouldn’t be any better.

  5. AFAIK as long as you do a CP -a it doesn’t really matter.  I would just use rsync from the start.

  6. Rsync or safepoint is the way to go.  Or any backup solution you know will work (manual or auto) and you trust.