How many LTO Tape drives are you using?

[jreale]

Hi everybody!



We are going to purchase a LTO Ultrium Ultrascalable tape library 3584 model L32, but I don't know yet how many drives we need for running TDP for R/3 (Oracle) on IBM 6M1 RS/600 in under 4 hours.

There are 8 CPU's (750 Mhz) with memoria real = 10 GB. The SAP database's size is about 1.700 GB or 1,7 TB. The TSM Server 4.2.2.10 are running on IBM MB80 RS/600. The TSM server is on the separate physical server from SAP database.

We are using disks SHARK IBM.



So, please tell me how many drives recommend to allocate in Library 3584 in order to take a SAP database backup in under 4 hours. Or could you tell me how many drives are you using actually.



Thanks in advanced.

[email protected]

 

[heada]

jreale,



I have a somewhat wimilar setup. I am running SAP on Oracle at 1.8 TB on an ESS. My SAP servers are SP attached S80s with (12) 600Mhz processors and 8GB or real RAM. I am writting directly to 3 fibre attached 3590 drives and can do a complete offline backup in 4.5 hours. My TSM server is an SP WinterHawk II node.



-Aaron

 

[jreale]

Hi, Aaron.

I have the following questions:

1)-What kind of network do you have between the TSM server and the SAP database?

2)- What kind of switch are you using to connect between those servers? Is the SAN-switches are 1Gbit /sec?

3)- How many multiplexing's are you using in TDP for R/3?

4)- Which version of TDP for R/3 are you using?

5)- Are you using multiple paths simultaneously or Parallel Backup Paths? If yes, how many paths do you have? Could you tell me how to make it in order to improve performance of backups?

6)- How many fiber adapters (HBA) do you have for drivers on the server SAP database and/or TSM Server?

7)- If you have a diagram of connection among all servers, could you send me it in order to know how connection are you using?

Big thank. I very much look forward to hearing from you.

Regards.

Juan R.

 

[heada]

1) I have an SP2 High Speed Switch It's rated at 180MB/s

2) The hosts are direct connected to the ESS with (4) 1Gb/s connections. I have also tested (2) 2Gb/s connections via 2109-S16

3) 3 sessions - 3 multiplexing (total of 9 files at once)

4) TDP for R3 v 3.3.2(fixed install)

5) I'm not sure what you mean by this. I am using DPO on the ESS side with 4 paths to the disks

6) On the SAP side, I have 4 HBAs to the ESS and 1 HBA on the TSM server. I use the rule of 1HBA per 4 3590Drives (so I can get a full 25MB/s per drive)

7) I don't have a diagram, sorry.

 

[jreale]

Hi. Thank you for your response. I have the others following questions:



1)- Are you using SAP Database's Online backup? If not, could you tell me why you are not using it. If so, how long this backup lasted.

2)- Is 2109-S16 a SAN Fiber Channel Switch? Is it directly connecting to LTO Drivers too? how many switch’s you are using? It is connecting with ESS, LTO Drivers and SAP Server, it isn’t? or if not, which switch’s you are using as intermediate between the 2109-S16 Switch and LTO Drivers.

3)- Do you guess this backup’s time will be reduced till 2 hours if we allocate two more LTO drivers?



thank you again.

 

[heada]

1) Yes, we are using the BRBackup function for both online and offline backups (actually doing archives to TSM) I am NOT using RMAN. I am also using TDP for R3's compression since it is much better then the TSM client's compression.

2) A 2109-S16 is the IBM branded 16 port gigabit fibre switch(actually a Brocade Silkworm switch). I run all my tape drives throught this. I also run non-production ESS connections through it. I have 6 switches (3 per SAN, dual connection)

3) In our testing, the law of deminishing returns comes into effect when we add more then 3 drives. Adding a 4th drive didn't decrease the backup time enough to warrant having a 4th drive allocated. I would suggest you do trial and error to find the sweet spot for your setup.



-Aaron

 

[jreale]

According to the last your message, you told me that you could do a complete offline backup in 4.5 hours, but I need to know how long the SAP Online Backup lasted. Did it finish more time than the Offline backup? If so, why?



Thank and regards.

Juan