TSM upgrade

[THE_WIPET]

Hi all

We have a TS3500 with 8 LTO3 drive serving 3 TSM instance on a single server. Total amount of data(online and vault = 266TB) We are actually looking to upgrade the number of drive. We are looking at 3 possible scenarios.

1- ADD 6 LTO3
- Patition de library with 10/12 LTO3 with 3 TSM Production instance on 1 single machine and 2/4 LTO3 for DEV(New Env) a single machine.

2- ADD 6 LTO4
- Partition de library with 6 LTO4 for our main TSM Instances. 2/4 LT03 drive for the other instance(less critical) and 2/4 LTO3 for DEV(New Env) on a single machine

3- (This depends on the budget we have) ADD More than 6 LTO4 with replacing some of the LTO3 Drives.
- Partition de library with the amount of LTO4 drive for the 3 main production instance and the rest to the DEV(New Env) on a single machine.

I know that activating partitionning add a little more complexity for tape management and my goal is to keep the backup infrastructure simple as possible with the usual upgrading the performance and capacity.

My concern is should i stick to LTO3 and plan for a mega conversion in 2 or 3 years to the new technologies our grab the oportunity and start switching to LTO4 and live for a year or more with mix technologies.

I know LTO4 are fully compatible with LTO3 tapes and what are the pros and cons living with the 2 of them.

Thanks for any advices

 

[THE_WIPET]

Sorry... i should name the tread library upgrade

 

[molerio]

Capacity Planning

You wanted to keep this simple right?

Instead of partitioning the library, Why don't you make one instance (or add a small instance) the library manager and share all the drives/scratch tapes with all the instances?
This way you don't have to partition the library and you can use your option # 3 to eventually migrate the lto3 volsers to lto4.

 

[THE_WIPET]

molerio

Thank fo the info, as i said "Keep it simple as possible"

Our setup is already using a library manager (3 instances on 1 physical server) but i was under the impression if you have another physical server accessing the same librairy, you need to partition it. If not it will simplify the setup. i'll dedicate some path to particular instances.

The other thing i forgot to tell is one of the server(DEV) will be physically in an other building and will access the library throught the MAN/SAN... So thats why i was looking for the partitionning of the library... if using the library manager and still going throught the SAN.. i'm a happy camper!

 

[djchopps0013]

We currently just replaced 20 lto3 drive with lto4 in one library. We have two servers accessing this library. Library is shared not partitioned. We currently write on lto3 and lto4 media. We have found no issues with the setup at all. What we did have to do is up our fabric to 4GB in our tape SAN infrastructure to accommodate the increase in transfer rates on the LTO4 drives.

Hope this helps

 

[molerio]

capacity planning

Then just add the dev instance ( library client) and define the drives & paths to the it.

 

[THE_WIPET]

Thnks for all the information.

I got one last question... Is the library client need to be at the same version.... EX: DEV ENV. is TSM 5.5 and PROD (library manager) is 5.3 until the migration...

 

[molerio]

capacity planning

I'm not sure best to ask IBM I'd go with the same version to be safe.

 

[THE_WIPET]

hey molerio

i've talk to our IBM friends.. What they told me was that the lib manager has to be the highest version.