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Multi-thread with hard disks?

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I used Retrospect from literally version 1.0 to ugh! version 8, I then gave up on it.  :(

 

I started off with TEAC data cassettes, moved to AIT tapes (various generations), briefly in comparison used LTO tapes, and then finally ended up using hard disks in a drive dock as these became a cheaper, bigger capacity and supposedly faster solution than tapes. I say supposedly because Retrospect became a sick joke in terms of performance.  :(

 

At the time I moved to version 8 I also moved from Retrospect 6 on a Dual Processor PowerMac G5 with 2GB of RAM and a SCSI card and using tapes, to a Mac Pro with octuple cores, 24GB of RAM, and eSATA connected drive docks with SATAIII disks. It was if anything slower.  :( (The Mac Pro also had an eSATA PCI card supporting SATAIII, in theory this should have been far faster than FireWire 800 or SCSI.)

 

(You will note I deliberately said 'moved to version 8' as it could hardly be described as an upgrade - ugh!)  :(

 

One of the big disappointments in version 8 was the claim it was supposed to be able to do multiple backups at the same time assuming you had multiple backup devices. I never got this to work. Remember I was using hard disks as the backup medium not tapes. The main purpose of this post is to ask if Retrospect 11 will allow backing up multiple clients to multiple hard disks, more specifically as an example if I have the multi-server version with no addins will it be able to backup ServerA to diskA, and ServerB to diskB at the same time.

 

I am extremely wary about the idea of moving back to Retrospect, I have seen some reports from users suggesting version 11 is a big step forward compared to 8/9 and the new feature of block level incremental backups sounds very attractive. However the problem with Retrospect has never really been down to features but the fact that even with version 6 and certainly 8 & 9 it had a miserable level of performance and again with 8 & 9 a truly awful level of reliability. The reviews even the recent ones on MacUpdate do not inspire a great level of confidence.

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I can confirm that in our setup, we can simultaneously back up three client machines using Retrospect 11: two clients to two different disk media sets and the third client to a tape media set.

 

Retrospect 8 was definitely not ready for prime time.

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I can confirm that in our setup, we can simultaneously back up three client machines using Retrospect 11: two clients to two different disk media sets and the third client to a tape media set.

 

Retrospect 8 was definitely not ready for prime time.

Thanks that's good news.

 

Would you say Retrospect 11 is able to handle backing up 1million+ files from a volume without problems? This is where Retrospect 6, 8 and 9 used to struggle when doing the 'cataloging' phase of this large amount of files. It would spend hours doing the cataloging and you could see that it was not writing to or reading from any disks. It seemed to be CPU bound as it was running 100% of a single CPU core - so it was also not multi-threaded when doing the cataloging.

 

Unfortunately it would not at the same time do a pre-scan of the next server in the list so this tied things up badly.

 

I would now have some server volumes with 3 or 4million+ files on. One is a mail server so no - splitting the files across more smaller volumes is not an option.

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I can confirm that in our setup, we can simultaneously back up three client machines using Retrospect 11: two clients to two different disk media sets and the third client to a tape media set.

 

Retrospect 8 was definitely not ready for prime time.

 

PS. In theory a single hard disk backup set being a hard disk is a device capable of supporting multiple simultaneous sessions. Therefore again in theory more than one client could be being backed up at the same time to the same hard disk. I suspect the answer is no but does anyone know if this is possible?

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In theory a single hard disk backup set being a hard disk is a device capable of supporting multiple simultaneous sessions. Therefore again in theory more than one client could be being backed up at the same time to the same hard disk. I suspect the answer is no but does anyone know if this is possible?

No, it is not possible. A media set's catalog is commandeered by whatever activity accesses it first, and a second activity needing the same media set can't begin until the first activity has finished.

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I would say "yes, it's possible". I'm using 2 disks on my Retrospect backup Mac. On those disks I have created numerous disk media sets for the clients I want to backup. And I can run multiple Retrospect backups at the same time to the same backup disk.

As I'm writing this, 4 backups are running in Retrospect right now:

- The Retrospect Mac itself to disk 1

- Client 1 to disk 1

- Client 2 to disk 2

- Client 3 to disk 2

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