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Client side deduplication option with Datadomain

Level 3

I know that client side deduplication doesn't work with datadomain. However, if client side deduplication is enabled in the backup policy, will there be a loss of performance here? or does it work like disable already? The point I was wondering is that I have experienced many times before that I have observed an increase in backup time when client side deduplication is enabled. Although this option does not work with Datadomain, may it be possible for this option to be delayed on the client side?


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Client dedupe cannot be enabled in a backup policy - Accellerator can be enabled and client-side-dedupe can be disabled in a policy.

The default in NBU is Media server dedupe. Client-side dedupe is enabled in the master server Host Properties -> Master -> Client Attributes. Client names need to be added here, and then the option needs to be enabled by selecting options under "Where deduplication should occur". The choices are: 
- Always use the media server (the default)
- Prefer to use client-side deduplication
- Always use client-side deduplication

I think that if the last option is selected, the backup will probably fail. Just my thought. 
You can always try one client and see what the result is. 

'Prefer to use client-side deduplication' will default back to media server dedupe. 

Further to what @Marianne has said, enabling client side deduplication (CSD) in the client atrtributes will have no noticable effect on the backup success when the storage unit is a type unsupported for CSD. What you will see in the job details is something similar to this:
<date> - Error bpbrm (pid=4572) Unsupported storage server type (hp-StoreOnceCatalyst) - disabling Client Direct
The backup will continue and (all other things being equal) complete without further problems.

So you are unlikely to notice any speed/duration degradation if you leave this attribute set to either use CSD always or preferred as the handshake step is insignificant in relation to the entire backup.


I would make use of Media server resources to do the dedupe computing.

You know, app or server owner are not bothered about backups until they loose something, they want the app to perform well & want all the compute on the client used by the app instead of sharing with NetBackup client dedupe process. Certainly the usage will reduce after the first Full backup but dedupe will still try use the CPU cycles whenever the backup runs. Try avoid dedupe on the client side unless you system architecture is robust enough to handle the uncertain CPU bursts.