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arctics2's avatar
arctics2
Level 5
11 years ago

Duplication Backlog

Hello, We are in the process of implementing 2 Netbackup 5230 appliances.  The plan is to use SLP's with AIR to replicate backups to the remote appliance and to duplicate to tape.  The problem is t...
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  • mph999's avatar
    mph999
    11 years ago

    ... but don;t forget, the duplications have to happen while the drives also cope with the regular day-to-day stuff ...

    Without knowing exact details it's impossible to make any accurate comments.

    Based on what I have seen in the past ...

    What usually happens, is that SLP is an after thought and many systems do not have sufficient throughput to cope with SLP, hence the big demand for SLP windows (which arrived in 7.6).

    (Not saying that SLP shouldn't have had windows in the first place ... )

    Anyhow, when we see issues with cases were for whatever reason, an SLP backlog has built up, sometimes for even just a few days, if the system only just has enough capability to cope with the normal duplications each day, it can be impossible to catch up.

    So it comes down to how much idle time the drives have that can be used to tackle the backlog.  I would also consider that appllicable tuning might need to be applied in various areas to cope with the extra demand a months worth of backlog will place on the system (nbrb, emm etc ...).

EnriquePereira's avatar
EnriquePereira
Level 5
11 years ago

I do not think you will have issues. As the appliances are new, there will be little fragmentation on the pool and rehydratation should work at good speed. 

You probably could get something between 100 and 200MB/seg duplicating to tape, so 15 TB will take between 1 and 2 days (of course, this is only a estimation, please tell when you run it what is the real speed). Maybe during duplication to tape could help to suspend the source duplications (not the backups, just the air duplication).

As a trick, you can select convert to primary copy the copy that goes to tape. This can be a easy way to track wich images you have left on the msdp pool to duplicate to tape (the primary ones are still not replicated). Later you can convert again the MSDP image to primary when you finish the tape out.