Replacing LTO4 drives with LTO6

[amirjaffri]

Hello Everyone,

Does any one know a step by step procedure for replacing the Tape drives.

Current configs:

2 sites with SL3000 Tape Libraries controlled by seperate media servers on each site.

Each side has 16 Fiber attached LTO4 tape drives.

Each side has multiple NDMP hosts configured with locally zoned tape drives.

Besides new Zoning what needs to be done?

Do we have to reconfigure Robots (WWPN for Libraries will not change)

Do we have to rescan all the drives on each media server or is there a short cut to avoid that?

Do we have to reconfigure tape drives on all NDMP hosts?

Thank you for your help.

Amir

[SymTerry]

Really not much that needs to be done. Just delete the drive old drive using tpconfig -delete -drive, or in the GUI. Re-zone the new tape drive and make sure the OS can see it. Then add the new drive with the hardware wizard or tpautoconf -a

If your going from LTO 4 to 6 then please make sure you have LTO6 tapes ready to write as you will only be able to read LTO4 tapes with that new drive.

There is also a doc on How to update NetBackup for a replaced tape drive without deleting and re-adding the drive

Also refer to the NetBackup 7.6 Administrator's Guide, chapter 7, Configuring robots and tape drives. 

[amirjaffri]

Thank you SymTerry,

I will go through the document links.

regards,

Amir

[mph999 · Accepted solution]

The LTO6 drives will only be able to read the LTO4s, not write to them.

However, to be allowed to load the tapes, the LTO4s must be the same density (hcart, hcart2 etc ) as the drives, so whatever density the tapes are now, you will have to make the drives (LTO6) the same density.

You will need to use a new volume pool for the new drives, else if they are the same volume pool as the LTO4s, NBU will try and write to the LTO4s, which will fail, and then change the backup policies to use this new volume pool.

In other words, the LTO6 drives need to be the same density as ALL the tapes (LTO6 and LTO4) but be prevented from wroting to the LTO4s, and the only way I can think to do this, is to use a volume pool for the LTO6s that is different from the LTO4s.

As the LTO4s have data, you cannot change the pool, hence the suggestion of a new one. This makes no dfference to the operation of NBU, the volume pool is simply a virtual container, the name makes no difference (with the exception of the special pools like NONE (cleaning tapes) and Catalag pool.

For the catalog pool, I would leave this alone, and SUSPEND (Not Freeze) the existing catalog tapes (or remove them from the liabrary).

Regarding Symterrys post - the easiest way to swap the drives is to delete and readd.

[amirjaffri]

Thank you mph999, we are planning it on February 17th., 2015. I will let you know how it goes.

[Marianne]

My 2c:

Add LTO6 drives and media as different density (NBU default is hcart3).

When you want to restore from LTO4 media, change one LTO6 drive temporarily to match LTO4 media density (e.g. hcart). Change back after restore has completed.

In this scenario, there is no need for new volume pools.

[amirjaffri]

Thank you Marianne,

We discussed in our team to keep one drive on each site to be hcart for LTO4 restores to avoid restarting the ltid. If there is a way to change the density without restarting ltid, it will be awsome to know.

Amir

[mph999]

No, you cannot change the density of a drive without restarting ltid.