I'm doing this at 2 different customer sites. 16 MB/s seams slow to me. LTO 6 can theoretically go 160 MB/s and I've seen DD620 sustain over 100 MB/s on restores. My two sites are using DD620's and go around 20 MB/s when cloning to tape but they are also not setup optimally. Do you have more than one storage node? If so I'd start with confirming Networker is using a storage node on the same lan as both the data domain and tape drive.
It depends how you do it. I clone in a way that I create list of ssids and then I create input file for each DD volume. Then for each list, I run nsrclone and that goes fast.
I'm duplicating from NetBackup (NBU) backups to tape - attempting in the last couple of weeks
Set-up and what the problem looks like.
Local media server has the NBU OST plug-in that moves the deduping from the DDR controller to the media server. The idea is to reduce the stretched LAN traffic between data centres. The target DDR is in the remote data centre. This all works fine.
Once the primary backup is on the remote DDR its copied to a local tape library that has 4x LTO-5 tape drives.
Problem as I see it.
The total copy rate from the DD4500 to the 4x LTO-5 tape drives is only 100-120MB/s which is pathetically slow. I would have expected at least 100-120 MB/s for each of the four tape drives All IP interfaces are 10GbE and thoroughly tested using using IPERF - they perform as advertised. The LTO-5 is on a 8GBFCP interface and works fine if its not a duplicating job.
The likely cause seems to be very slow rehydration speeds of DDR. At the moment trying to prove that. Next step is map a CIFs share and copy the data to NUL and do the same with NFS and compare. Plus test to see what happens witrh multiple copies running at the same time.
We clone to T10000's and it takes about 1 day per TB. My limitation right now is network interfaces. The data domain has 12 Gig interfaces configured in a pool, however my networker server that handles translation from Ethernet to fiber channel only has a single 1gb interface.
So I'm limited to the maximum throughput of that networker interface. minus administration, and any other backups or restores running at the time that don't use Client Direct.
What is the path your data has to flow to get from Data Domain to Tape?
I have done this on several deployments, but actually flipped the model going from Tape to DD. DD units have phenomenal write performance, but they are slower at read from drives. If you backup to tape and then clone from tape to the DD you will get better performance overall and actually test your tape restore in the process.
You should be able to backup to tape and to the DD at the same time so you are not penalized by going to tape first.
i've implemented DD boost over FC from DD to LTO-6 tape at a client site and getting about 80 MB/s average speed per tape drive. We have 2 tape drives in the environment. Just wondering if anyone knows if we can get some better performance here or if that's probably about as much as we can expect.
Ryan_Johnson
73 Posts
0
May 28th, 2015 14:00
I'm doing this at 2 different customer sites. 16 MB/s seams slow to me. LTO 6 can theoretically go 160 MB/s and I've seen DD620 sustain over 100 MB/s on restores. My two sites are using DD620's and go around 20 MB/s when cloning to tape but they are also not setup optimally. Do you have more than one storage node? If so I'd start with confirming Networker is using a storage node on the same lan as both the data domain and tape drive.
ble1
4 Operator
•
14.4K Posts
0
May 29th, 2015 01:00
It depends how you do it. I clone in a way that I create list of ssids and then I create input file for each DD volume. Then for each list, I run nsrclone and that goes fast.
Jim-10
7 Posts
1
May 31st, 2015 21:00
I'm duplicating from NetBackup (NBU) backups to tape - attempting in the last couple of weeks
Set-up and what the problem looks like.
Local media server has the NBU OST plug-in that moves the deduping from the DDR controller to the media server. The idea is to reduce the stretched LAN traffic between data centres. The target DDR is in the remote data centre. This all works fine.
Once the primary backup is on the remote DDR its copied to a local tape library that has 4x LTO-5 tape drives.
Problem as I see it.
The total copy rate from the DD4500 to the 4x LTO-5 tape drives is only 100-120MB/s which is pathetically slow. I would have expected at least 100-120 MB/s for each of the four tape drives All IP interfaces are 10GbE and thoroughly tested using using IPERF - they perform as advertised. The LTO-5 is on a 8GBFCP interface and works fine if its not a duplicating job.
The likely cause seems to be very slow rehydration speeds of DDR. At the moment trying to prove that. Next step is map a CIFs share and copy the data to NUL and do the same with NFS and compare. Plus test to see what happens witrh multiple copies running at the same time.
See : Very slow throughput in SLP duplicatkion jobs | Symantec Connect
Symantec says my set-up looks OK and tuned appropriately
Davidtgnome
1 Rookie
•
66 Posts
1
June 2nd, 2015 07:00
We clone to T10000's and it takes about 1 day per TB. My limitation right now is network interfaces. The data domain has 12 Gig interfaces configured in a pool, however my networker server that handles translation from Ethernet to fiber channel only has a single 1gb interface.
So I'm limited to the maximum throughput of that networker interface. minus administration, and any other backups or restores running at the time that don't use Client Direct.
What is the path your data has to flow to get from Data Domain to Tape?
paul_aviles
31 Posts
0
August 23rd, 2015 08:00
I have done this on several deployments, but actually flipped the model going from Tape to DD. DD units have phenomenal write performance, but they are slower at read from drives. If you backup to tape and then clone from tape to the DD you will get better performance overall and actually test your tape restore in the process.
You should be able to backup to tape and to the DD at the same time so you are not penalized by going to tape first.
Paul Aviles
ksun87
32 Posts
1
December 16th, 2015 14:00
i've implemented DD boost over FC from DD to LTO-6 tape at a client site and getting about 80 MB/s average speed per tape drive. We have 2 tape drives in the environment. Just wondering if anyone knows if we can get some better performance here or if that's probably about as much as we can expect.