The savings will result from tape backup infrastructure the company will not have to purchase as a result of implementing Quantum disk-based data deduplication backup hardware that has achieved data reduction ratios of up to 20:1.
The upgrade was carried out as part of a £20m technology refresh of the private cloud common delivery infrastructure (CDI) by Serco’s global technology division, which supplies IT to the company’s 110,000 staff and its customers worldwide.
Serco’s private cloud CDI was established five years ago for a small number of clients, based on tape storage, but by 2010 had begun to outgrow its existing infrastructure. At that point the company decided to move to generation two of CDI and set out to overhaul the technology.
Serco's senior infrastructure consultant and owner of storage, Mark Owen, said the biggest problem was storage and, in particular, the space required. “By 2010 we had 45 tape drives in our Quantum i500s and a full backup was taking 70 hours at the weekend. With the growth we were experiencing that would soon have become unacceptable,” he said.
“We now have 34 CDI customers with 2.8PB of data and would need hundreds of tape drives. We just don’t have the space for that,” he added.
Owen’s team evaluated data deduplication disk-based backup hardware from EMC Data Domain and Quantum. Data Domain was more expensive, but a key attribute that attracted Serco to the Quantum DXi appliances was that its data deduplication algorithm produced better data reduction ratios.
Serco eventually implemented four Quantum DXi8500 disk-based backup appliances with 50TB of capacity each in two pairs at each of its two Birmingham datacentres, with synchronous replication between the two active sites. CommVault backup software is used to protect around 2PB per month of customer data.
Quantum’s DXi disk backup appliances can operate as a network attached storage (NAS) device, virtual tape library and data deduplication device. Data deduplication is carried out at the target, with data reduction carried out inline rather than post-process following data ingestion.
Serco has retained the Quantum i500 LTO-4 tape libraries for longer term retention, and around 60TB per month is shipped to tape.
This backup and archiving infrastructure supports CDI infrastructure of around 260 HP and IBM servers running approximately 1,000 virtual machines.