Posted by: Dave Raffo
data backup, data deduplication
Just about all data deduplication vendors make claims about the dedupe ratios their systems provide, with the caveat that the ratios vary by data type and backup frequency.
Sepaton today says it’s willing to guarantee its ratio for Exchange. The VTL vendor said if customers don’t get a 40:1 ratio with its DeltaStor dedupe software in 30 days, it will throw in a free disk shelf with at least 7.5 TB of capacity – a $50,000-plus value.
There are some conditions. First, the customer must use Symantec NetBackup for now, because that’s the only backup software DeltaStor supports. And the customer must do daily full backups, which result in better reduction than incremental backups. The guarantee is part of what Sepaton calls a FastStart Deduplication Package for Symantec NetBackup, consisting of an S2100-ES2 library with 20 TB and DeltaStor.
Analysts who closely follow the dedupe market say Sepaton deserves credit for making the guarantee, but isn’t exactly sticking its neck out. Because Exchange includes a lot of messages sent to multiple recipients with attachments, it tends to have a great deal of duplicated data that can be reduced.
“To guarantee anything takes guts,” Arun Taneja of the Taneja Group said. “It’s a good marketing strategy for them to set the trend and draw a line in the sand. But for full backups for email for 30 days, 40:1 is very achievable. So I would say it’s not a very large risk.”
Glasshouse backup guru Curtis Preston agrees. “I think it’s a great idea and I doubt they would have done it if they hadn’t already done a lot of testing to verify they actually can get more than 40:1 in most Exchange environments,” he said. “There is a lot of duplicate data in Exchange.”
Sepaton director of product management Jim Shocrylas said the 20 TB system would give a customer with 4 TB of daily full backups a retention period of about half a year. He said the guarantee applies to full backups because Microsoft’s best practice recommendation for backing up Exchange is daily fulls.
“This is first of a number of guarantees we’ll be coming up with for specific data,” Shocrylas said. “Others will follow.”