Tape not cutting it? EMC next Monday will announce the Clariion Disk Library, which according to EMC Vice President of Platform Marketing Chuck Hollis, is "at a high level, a functional replacement for a tape library."
Aimed at enterprise customers that don't quite need remote replication, Clariion DL can be seamlessly inserted into an existing backup environment, emulating popular tape libraries from companies such as ADIC, Quantum ATL, and StorageTek. Clariion DL can also automatically initiate the process of making a tape copy for offsite storage, circumventing the backup server.
Virtual tape, in other words? Not quite, Hollis says. Whereas virtual tape helps you meet your backup window by acting as a staging area, Hollis says, Clariion DL is "architected to help you recover." In other words, Clariion DL is designed to keep large numbers of backup images online and local, and to speed up time-to-recovery.
Whatever you want to call Clariion DL, "it's faster than tape, and it's more available than tape," Hollis says, even if "it's not cheaper than tape."
Let's take those points one by one. With single stream performance of up to 80MB/s, assuming compression, EMC estimates that Clariion DL is about 30 – 60% faster than single stream tape performance (EMC measures LTO-2 performance at about 55/MBs at 2:1 compression, which includes the time it take to load/unload the tape media, find the file, etc.) Clariion DL can support sustained throughput of up to 425MB/s, or about 1.5TB/hour.
It's on the restore that things get interesting. Assuming a backup image is resident on the Clariion DL, EMC claims it can run circles around restore from tape. In its example, Clariion DL was able to restore 9GB of incremental backup data 90% faster than if that data were stored on three tapes.
Meanwhile, on the availability front, Clariion DL beats out tape for all the obvious reasons: it's RAID-protected (RAID-3, optimized for streaming write performance), and it's built around Clariion's "dual architecture" says Hollis, including redundant power supplies and fans. Nor does Clariion DL suffer from tape's more egregious flaws: faulty media, moving parts, etc.
But when Hollis says Clariion DL costs more than tape, he's not joking. Equipped with 5400 rpm 320GB Maxtor parallel ATA drives, EMC estimates that Clariion DL comes in at about 40 – 55% more than a comparable tape library, in terms of capacity and performance. Clariion DL's entry pricing is even more disheartening: base-line pricing is $109,000 for a barebones (700GB) DL300. Sample pricing for a DL with 32TB usable is about $450,000 – or a whopping $14/GB for 5,400 rpm ATA storage.
Clariion DL will come in two models: the DL300 and DL700. The DL700, which is based on the recently introduced Clariion CX700 system, delivers sustained performance of 425MB/sec and carries a maximum capacity of 58 TB of useable storage and up to 174TB using compression technology provided by the disk library. The smaller DL300 delivers performance of 225MB/sec and supports a maximum capacity of 12.5TB and up to 37.5TB compressed.
David Kadow director of systems infrastructure for CDC IXIS Capital Markets North America, has been involved in EMC's beta testing program since January and plans to have a Clariion DL700 disk library in production in about five weeks.
Kadow said he was skeptical about moving to disk as his primary backup option, but the DL700 outperformed his tape libraries and allowed him to scale down his tape systems. "I'm always suspicious of brand new paradigms in general. We've heard things and read announcements that have been extremely immature, even for shipping products," Kadow said. "We thought it was a great idea if it did work, but it isn't going to completely replace tape. We have upgraded our tape system as well, but the (DL700) allowed us to vastly scale down the tape solution."
Kadow expects the price tag for the DL700 to be about equal to what he would have spent on tape libraries, but the performance is going to outshine his existing DLT tape systems. "In terms of percentages we're probably going to end up about even, but the performance is going to be better. [In testing], the performance of the Clariion DL proved to be up to 10 times faster per stream than we would see with DLT."
Kadow said he plans to add a 48TB DL700 to its data center to speed the performance of his backup operations. CDC IXIS North America backs up about 6TB of data per week.
EMC has stiff competition on the virtual tape front. Dianne McAdam, senior analyst and partner at Data Mobility Group, on the virtual tape front Dianne McAdam, senior analyst and partner at Data Mobility Group, estimates that there at least 20 vendors with virtual tape offerings right now, ranging from StorageTek and IBM, with their venerable virtual tape offerings, to software-only players such as NearTek and FalconStor, which bundles its software on an intelligent switch platform from MaXXan.
All that competition will wreak its usual havoc on price. As with any product, "there are two kinds of prices – list price, and street price," says and the two vary wildly.