01/17/2011 07:43 AM

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The issue being raised in this message relates to the use of the Drobo and Time Machine for backup. The process has virtually ground to a halt unfinished. See details in attached document.

I have no further ideas about what I can do to obtain improvement in the backup process. The TimeMachine backup process is just getting slower and slower, to the point that it is just not a viable system. ) I am thus hoping that I can get assistance from Drobo Support to advise me on how I should resolve my issue.

Many thanks

Name, address, email address, telephone numbers all supplied.

Instead of attaching a document to this post I have include the text of the document below.

Dear Support

For home use I recently (early January 2011) purchased a Drobo (serial number TDB10387xxxx) in the UK. I also purchased 5 Seagate Barracuda LP 2TB 5900rpm 32MB Cache 3.5" SATA 3.0Gb/s Hard Drives to populate the Drobo.

The purpose of the Drobo is to provide a storage system for Time Machine backups from a Dual 2GHz PowerPC G5 (PowerMac G5) system, a 2.66 GHz Intel Core 2 Duo iMac iMac, a 2.5GHz Intel Core 2 Duo MacBook Pro, and a 2GHz PowerPC G5 iMac. My concern is however with the PowerMac backup as it is my main system. I haven’t yet backed up the MacBook Pro or the older iMac.

I have the Drobo, the PowerMac and the 2.66GHz iMac on a GigaBit Ethernet LAN. Basically a ZyXEL GS-105B 5 port Gigabit Unmanaged Desktop Switch connects through a CAT 5e cable to the GBit Ethernet port on a Vigor 2820 series ADSL modem/router. The computers connect to the ZyXEL using CAT 5e cables.

The PowerMac desktop system, however, is the only machine with any significant disc storage. It has 2x1TB internal discs, 2x5TB Sonnet Fusion D500P storage systems and a number of external firewire and USB2 drives. The issue being raised in this message relates to the use of the Drobo and a Time Machine backup from the PowerMac system. The desktop system runs under Mac OS X 10.5.8. The backup to the 2.66GHz iMac works perfectly but it has very little data – only around 200GB.

At the moment one of the Sonnet arrays is used for the TimeMachine backup on the PowerMac. The internal discs in the PowerMac are used only for applications – no (very little) data. One internal disc is used as a bootable mirror of the other. It is my intention, once I get the Drobo/TimeMachine system to work properly I will used one of the Sonnet arrays as a mirror of the other. The Drobo will thus be a second line of defence against loss of data.

External USB2 discs are currently used for backing up the other systems.

My TimeMachine backup is only a selection of the data from the drives on the PowerMac – ie lots of exclusions. The data being backed up is only around 2.5TB. I have set up a TimeMachine enabled share of 5TB for this purpose.

To facilitate an iterative approach to the creation of the intial TimeMachine backup process I only permitted Drobo to backup some of the data. Once that was done successfully I deleted exclusions and allowed more data to be backed up. As was expected it was slow. 10GB/hour average was transferred for the first few iterations. One iteration gave me approximately 20GB/hour. But my most recent iteration when I was trying to backup a further 450GB from one of the Sonnet drives gave an average of 0.5GB/h over a 24 hour period.

I read all I could find in forums and on the Drobo site, upgraded the firmware to 1.1.0 and then tried again. Still the backup from that drive is snail like. Hopeless in fact.

To check Drobo and the LAN I transferred 185GB (47,500 files) directly from the Sonnet drive in question to a new Share on the Drobo. It transferred in 3 hours and with very acceptable transfer speeds - consistently higher than 25MB/s were obtained.

The problem thus seems to be the TimeMachine/Drobo interaction/implementation as I have successfully been using TimeMachine to a Sonnet array.

I have no further ideas about what I can do to obtain improvement in the backup process (and I am at almost at the point of selling the Drobo and buying another Sonnet). The TimeMachine backup process is just getting slower and slower, to the point that it is just not a viable system. ) I am thus hoping that I can get assistance from Drobo Support to advise me on how I should resolve my issue.
Other information:

All drives in the Sonnet Arrays are 1TB enterprise quality. In the source Sonnet array there are 5 of Seagate Barracuda ES.2 - hard drive - 1 TB - SATA-300 Mpn: ST31000340NS. In the existing Sonnet array used for the TimeMachine backup there are 5 Seagate OEM ST31000340NS 1TB Barracuda ES-2,7200RPM 32MB Cache.

The Sonnets are connected to the PowerMac by a Sonnet Tempo-X PCI eSATA X4P Expansion Card.
Help would be most gratefully received. If you can advise me on a way forward please contact me.

Many thanks

Name, address, email address, telephone numbers all supplied again.