The London-based charity has raised more than £400m since 1985 largely through its annual flagship Red Nose Day. Its application portfolio is exclusively Microsoft, and includes several SQL Server databases, Office productivity applications and Exchange on 16 VMware virtual servers on four physical HP servers.
Storage for this computing environment had been provided by a Compaq RA4100 SAN with around 900 GB and two HP Proliant DL380 G4 NAS boxes with 6.6 GB between them. But with massive data growth, the charity had bumped up against the limits of that storage infrastructure and the storage environment had become difficult to manage. Allocation of storage for new projects was a particular problem, said Colin Buttle, network administrator with Comic Relief.
"We had hit a wall with the existing storage," Buttle said. "Data is growing exponentially every year and it was becoming fragmented – we had just enough space but in the wrong places."
At the same time, the organisation was running out of physical space to add more storage, so it was keen to find a solution that could provide a smaller physical footprint than the existing storage set-up, as well as limit growth in requirements for power and cooling.
Comic Relief opted for a Compellent SAN with 11.5 TB of capacity split between two enclosures and dual controllers with sixteen 300 GB Fibre Channel disks plus twelve 750 GB SATA drives. The SAN communicates with the VMware-based server environment (which was implemented at the same time) via a QLogic Fibre Channel switch. The organisation has also implemented Compellent's snapshot technology, called Data Instant Replay, and its Dynamic Capacity thin provisioning.
Thin provisioning allows the user to provision volumes to applications virtually in advance, while only providing physical provisioning when existing drive space nears capacity and physical disk space is required. Thin provisioning and tiering of data can cut down on the usage of power and cooling because disk that isn't used does not have to be powered and less frequently used data is shifted to drives that cost less to purchase and power.
Data stored by frequency of use
According to Buttle, one of the key benefits of the Compellent set-up is that the software automatically stores data according to frequency of use, with the most frequently used data going to the Fibre Channel disks. "Comic Relief is not an organisation that dictates how people work, so there is not a lot of housekeeping and therefore a lot of stuff is not frequently accessed," Buttle said."So most data is on the lower tiers and we have a lot of space on the top tier disks. I very much doubt we'll have to add more Fibre Channel drives."
Buttle added, "Moving data to lower cost media is also a benefit, as is being safe in the knowledge that we will not outgrow the size of the SAN and have to rip and replace."
Another benefit of the implementation has been to consolidate Comic Relief's storage, which is an important consideration in space- and power-constrained central London; as well as to allow more efficient management of resources. "We are very short of rack space and power in what is not a dedicated comms room," Buttle said. " Also, our data was all over the place -- file and print was on the SAN and it grew so we had to split it with one of the NAS boxes, which also started fast running out of space. Now we have been able to get all our data into one place."
Comic Relief – previously a 100% HP shop when it came to servers, chose Compellent over two HP products. It rejected an HP StorageWorks EVA 6100 Enterprise Virtual Array because, Buttle said, "the EVA 6100 was more expensive and did not offer as much as the Compellent product," and a StorageWorks 1000 Modular Smart Array, which he said was "an entry-level system that would have been maxed out from the word go."