Should we invest in Single Instance feature

[simple99]

I'm hoping someone can help clarify the Commvaults SIS feature in Simpana.

We're looking at upgrading from our current version 6.1 and found that the most expensive part of the setup is the license for 'Single Instance Disk Library Premium Connector'

As I understand it, this SIS feature reduces the size of data backed up to tape. Not the actual data in the storage used by the users.

Would it be better to instead invest in a proper deduplication appliance (ie: from Data Domain) to reduce the actual data being stored by users. This would mean Commvault only backups the deduped data thereby reducing the backup time and size.

What are ur thoughts and how succesful has your implementation of SIS been in your area.

Appreciate any comments.
Thanks

 

[theravager]

I think CVs implementation of SIS is garbage especially considering the price of it.

It all comes down to the cost of your storage if you are using maglibs, if you a considerable size of data then a hardware dedup device sitting in front of the storage is decent value. If you don't have a lot of storage then buying raw disc is probibly the go.

CV needs to do a ton of work in this area as its still first generation. Most of the CV engineer staff ive talked to don't even know what you can do or can't do with it in generic circumstances.

 

[birky]

Hi

"As I understand it, this SIS feature reduces the size of data backed up to tape."

SIS is only supported to disk at this moment in time - if you single instance to disk and then take a secondary copy to tape then it unhash the SI.

Wouldn't say that SIS is garbage - works quite well if used for what it's intended

Configued it a couple of times and it all depends how many duplicate files you have in your environment - works a treat if you are just looking to retain more full weekly backups on disk - not sure how useful it will be in an archiving role though (unless you have many duplicate files)



Birky
CommVault Certified Engineer

 

[simple99]

thanks birky,

I've done some number crunching with our Storage Exec software that does duplicate file reports and found that there is about 20% duplicate data in our shared folders.
In your experience is that a amount of duplicate data?

I was hoping that there would be cost reductions in having to use less tapes when backing up for archival. Getting more full weekly backups on disk is good but not sure if its incentive enough to invest in the expensive SIS feature.

Wonder if there are plans to expand this SIS feature to tape archival as well?

regards

 

[theravager]

There was word when sis come out that they were implementing it in the near future for tape but i haven't heard anything for 12 months in this regard.

 

[birky]

it is on the 'roadmap' apparantely for SIS to tape - expect to see it in 8.0 (hopefully)

SIS is most productive on the backups side eg.
Week 1 - you do a full backup + incrs
Week 2 - you do a full backup and incrs - you will probably find that you only hold on disk about 20% extra by the end of week2 (dependant on your rate of change) as you already hold most of the files from week1 full backup

For archiving if you say that 20% is duplicate files then I would say that SIS is a good move



Birky
CommVault Certified Engineer

 

[simple99]

thanks for the responses.

after reading on the subject more, I can also see that SIS is beneficial at making the most out of the secondary storage. Can hold onto more weekly backups before re-hydrating the data to tapes.

Just wondering what other SIS type (file based) deduplication software ppl are using ? I know the block leve deduplication appliance are expensive to implement and resource intensive.
Are there other system comparable to comvaults SIS that can working along with Commvault ?

regards