Netbackup hardware refresh?

[Flyinraptr]

Looking for some feedback/ideas from anyone who has been down this road before.  Currently running NB 6.5.2 on 1 Master and 2 Media Windows servers tied to an library with AIT-3 drives (SCSI interface).  I have a project that was just approved to replace all hardware ..... going to a disk-to-disk-to-tape solution using a new library with LTO4 drives and all new server hardware. 

My plan is to build a new NB environment in parallel to the existing NB enviroment - the new servers will also be Windows and running either NB 6.5.2 or 6.5.3.  Once the new system is up and running - the backup policies will be manually recreated on the new system and will slowly take over for the existing policies on the old system until the existing system is no longer running any day-to-day backups. 

Of course the big question is what about the existing AIT-3 tapes?   Do you keep enough of the old system around in case of restores or do you convert them.  One of the problems is the AIT-3 tape drives - vendor support will basically cease to exist by July of next year - so I'm thinking converting is the way to go, however, I will probably let the weekly and daily incremental backups expire and focus on converting the month/year end backups over to LTO4.    

One thought is to hang a few AIT-3 drives off of the new system .... import the tapes and then vault to LTO4.  Depending on the actual number of tapes needed to convert - this could take a long time.

Another thought is to merge the existing NB database into the new NB database - thus eliminating the import process but of course you would still need to vault the tapes.

Thanks - 

[sdo]

We're just putting a new system in production now.

Old: Win2000 NBU ES v5.1 MP6 stretch cluster, Sun V480R Solaris 8 medias, SSO, ADIC Scalar 1000s.

 New: Sun Solaris 10 NBU ES v6.5.2a VCS stretch cluster, Sun M5000 medias, SSO, VTLs, Quantum Scalar i2000s.

The new env is completly unaware of the old env.

We're currently migrating 500+ clients.  When this client migration is complete (and the old env is effectively read only), we'll zone in the old libraries, and begin importing about 900 x LTO1.  During this import phase we'll attach a new small library IBM TS3100 (LTO3) to the old env to be able to perform any required restores from the very old backups residing on LTO1.  When the import is done the old master and media servers can be scrapped, as we won't need the catalog anymore, we'll then begin duplication to VTL to LTO4.  When the data migration/duplication is complete the old libraries can be scrapped.

After investigating the many options, this was the simplest, least risky, least costly approach.

We did think of just leaving the old env to expire, but we've decided to get rid of the old env as quickly as possible.  We're going to utilise some spare HP DL580 G5 Windows media servers for the import, and as the old Scalar 1000s have 8 x LTO1 each, the imports won't take too long - as they can just be sitting there reading old tapes 24x7 - as these libraries will not be used for writing once they are zoned to the new env.

[Flyinraptr]

Sounds like a good plan ..... we are also running an ADIC Scalar 1000 in our old env - however using AIT-3 drives.  One of the issues I'm looking at is with the AIT-3's we average around 150GB per tape w/compression .... of course LTO-4 can handle 800GB natively - so a 1-to-1 duplication would waste alot of expensive LTO-4 tape.  The object would be to consolidate as many of the images on the AIT-3 tapes as I can onto the LTO-4.   I need to look at whether I can do that directly with vault or if I will need to duplicate to disk first and then to LTO-4.

[sdo]

Duplication is based on images not on physical media.  NetBackup will just keep appending to the LTO4 until it is full.  You don't have to worry about that.  BTW, across all our media (old env is around 500 TB) we average 2:1, so I'm expecting to see an average of 1600GB per LTO4.  Incidentally, even some of the old LTO1's contain 500GB (a 5:1 compression), but again some are a low as 95GB - just depends what gets saved when.

[Flyinraptr]

That's good to know.  BTW - are you encrypting your LTO4 tapes?   With the new system - we will be encrypting - curious to see how much that effects compression.

[sdo]

We don't use encryption at the moment, but I'd still like to know what the hit is.  We never send any tapes offsite.  We have dark fibre, and each site backs up to the other site, so essentially the media is already offsite by the time the backup completes.

I'm hoping that it won't affect compression, i.e. I hope they've implemented encryption in the tape head at the point after compression.  If so, then there shouldn't much of an added overhead, if any at all.  I guess the trick is not to use encryption from the client, but instead to encrypt at the tape head.

Does anyone have any useful links for background docs, white papers, etc on LTO4 encryption?