Data Flow during backup operation

[siri416]

Hi ,

My Question seems to be silly , I want to know how data flows when backup is performed.

Currently in my environment,we have DD , so my doubt is "Does the data flow from client to DD directly or it goes via Mediaserver to DD?"

[Marianne]

It goes through Media server to DD.

[mph999]

Adding to Mariannes excellent post ...

Data always goes via the media server ... unless ...

You are backing up the media serevr to itself, in which case it 'still goes via the media server' but as this is itself, you just see the data go straight to the storage, as it doesn't have to go over the physical LAN.

You are using SAN client - here the data goes via the media server still, but via the SAN

NDMP with drives connected directly to the NDMP device - here the media server still controls things, but the data goes stright from the NDMP device to the drives.

Things such as optimised duplication are a little different, here a device such as DataDomain would duplicate it's data directly to another DataDomain device.

This just about covers most thinkgs I think ...

Martin

[siri416]

Thank you Marianne and Martin ,

 So metadata will go through mediaserver to masterserver and original data will go through mediaserver to destination storage . And data will get de-duplicated at destination .

Incase of client-based de-duplication also , will data go via mediaservers ? please confirm

[Kiran_Bandi]

Metadata : Client --> Master Server.

Incase of client-based de-duplication also , will data go via mediaservers ?

Yes... Only unique data goes to storage through media server.

[Marianne]

No client-side dedupe is possible with DD. Only with NBU MSDP or NBU appliances.

With DD, client needs to send ALL data across the network to media server. DD plugin on media server will ensure unique blocks is sent from media server to DD.

[siri416]

Thank you kiran and Marrianne for confirming me this ,because someone told me that client will send data directly to dd not through mediaserver ,and mediaserver role is just to invoke processes

so just want to confirm,thank you

[Nicolai]

The rumor you have heard is likely form EMC. The latest version of EMC Networker let client talk direct with a Data Domain. NetWorker does not have any software based de-duplication option at all.

[teiva-boy]

Incorrect, Networker does have client side dedupe. But only when paired with DD and Boost or with avamar. No different than NBU as you need licensing, more ram, and storage. Its a wash in terms of cost and administration in many cases. Funny thing is that BackupExec can do client side dedupe directly to DD, but NbU cant. Go figure?

[Yasuhisa_Ishika]

I feel both you and Nicolai are right.
Networker does not have deduplication inside, but provide client side deduplication in conjunction with boost or avamar - deduplication is done in boost or avamar. Nicolai pointed this as "Networker does not have deduplication".