Advice Please!

[sqoil]

Hello!

 

 

 

Please help - any suggestions are appreciated!

 

 

 

Current Environment:

 

 

 

1) Retrospect 4.2

 

2) Mac0S 8 server

 

3) AIT1 (3MBits/sec) 4 unit tape library

 

4) 100Base T network (theoretically avg 7MB/sec)

 

5) Approx 11 AIT1 tapes (native 25GB compressed 50GB) on a typical job

 

 

 

I would like (to reduce the bulk of the work associated with the backup job) to move to an AIT3 unit and to run multiple simultaneous Retrospect client backups.

 

 

 

The benefits of AIT3:

 

 

 

(1) 4 times (100GB native) the capacity of AIT1

 

(2) 4 times (12MB/s) the speed of AIT1

 

(2) Backwardly compatible

 

 

 

The Problem:

 

 

 

Unfortunately i do not have 1000GBit capability (avg 70MBit/s) on my network so the problem is - if i go to AIT3, my network speed will be my bottleneck. AIT3 supports/requires 12MBit/sec transfer for optimal use and to avoid constant tape spin ups/downs. I am bound to 100 MB which averages 7MB/s transfers rate. If i go to AIT3 on my current network - the job will be even slower job

 

 

 

Potential resolutions:

 

 

 

1) Run Retrospect backup to disk then archive this to tape.

 

2) Etherchannel 2 100MBit cards to get 200MBit/sec (14MBit/s).

 

3) Run multiple versions of Retropect simultaneously.

 

4) Configure/hack Retrospect to stream from multiple nics at a time.

 

5) Do an expensive gigabit implementation.

 

6) Go to AIT2 (6MB/s)

 

 

 

I've talked to Dantz tech support and they indicate Retrospect does not support streaming a job across multiple independant nics (this capability is called using Media Servers in Veritas NetBackup). Does anyone have any advice on multiple Retrospect client backups? Teaming/Etherchanneling nics would (i hope) work - has anyone tried? Does anyone have any experience with option (1) disk backup then tape archive? Any other suggestions?

 

 

 

Thank you for ANY suggestions!

 

 

 

Sq

[sqoil]

Moving on in my investigations:

 

Retrospect does NOT support multiple simultaneous backups in the current version.

 

This means my 100Mbit (7MB/s) clients cannot be backed up to 14MB/s AIT3 tape directly.

 

I can either:

 

(1) Use a backup strategy of disk storage to later tape archival OR

(2) Go with AIT2 which integrates with my current 100Mbit network

(3) Wait for a new version of Retrospect

 

Still researching...

[AmyJ]

(1) Use a backup strategy of disk storage to later tape archival

 

This method is not recommended. Restores will be more then a little tedious considering you'll have to perform the execution twice (once from tape to disk, second time from disk to destination). In many enviroments the restore time is critical - especially when an entire machine crashes. The goal is to get it back into production as soon as possible.

 

 

Retrospect does NOT support multiple simultaneous backups in the current version.

 

That's correct. It is, however, a feature we hope to have in a future release.

[jallman]

1) Use a backup strategy of disk storage to later tape archival

 

This method is not recommended. Restores will be more then a little tedious considering you'll have to perform the execution twice (once from tape to disk, second time from disk to destination). In many enviroments the restore time is critical - especially when an entire machine crashes. The goal is to get it back into production as soon as possible.

 

Would this still be true if you do a transfer job from your disk backup set to the tape backup set? This is what we do daily since writing to our tape library is slow, and we don't seem to have problems going directly from tape to original source. All the snapshots seem to be contained in the final tape backup set.