Backup to disk questions

[hutchingsp]

Could I ask how you're finding it please?

Firstly a bit of context. We have our main server room which has an LTO3 library in it. We have a secondary location that has a smaller LTO3 library in it along with a server with local storage. The server, storage, and LTO3 are due to be replaced and I need to determine what to replace them with.

We currently using Galaxy 7 to backup to tape and usually do full backups to the main tape library, take them offsite on a Monday, and do incrementals to the second tape library so that if we lose the main server room we've got backups right until the previous night.

I'll most likely be sticking a bunch of disk space in the secondary location in the form of an iSCSI SAN or Storevault box, and I'm wondering if it's time I thought about doing backup to disk and then streaming this to tape.

I plan on speaking to a Commvault techie but wanted to get some feedback first.

The thing that leaps to mind is that with our current primary LTO3 library that is connected directly to our main file server, we can average around 350gb/hr on a full backup - around 100mb/sec and I'm not sure we'd beat that backing up to anything but a bloody quick disk array (assume on the end of a 1gbps connection)?

 

[Calippo]

You have to keep in mind that B2D (backup to disk) is mainly to enhance your recovery (RTO). However, with multiple data streaming inbound from the LAN you can also improve backup times but thats depending on how well your current storage policy can stream to tape.

It would be tricky to try and put a disk back backup against a pair of LTO3 or LTO4. However, if you wish to keep backups in nearline for rapid recovery then disk is the way to go. You can minimise your disk space requirment by incorporating Single Instancing.

Dont forget that you could also improve your back times by incorporating an HSM policy to move old data files or emails from Tier1 storage to Tier2, which is another good fit for a Magnetic Library (active archive).

In this B2D2T stratergy you still use tapes for long term storage for compliancy or to meet policy.

regards

---------------------------------------
EMCTA & EMCIE - Backup & Recovery
Legato & Commvault Certified Specialist
MCSE