Virtualised storagefrom 3PARdata
has helped USinternetworking (USi), the managed services arm of
AT&T, to stay competitive in the face of Web-based Software as
a Service (SaaS) competition, though the company is also pushing
3PAR for more advanced snapshot and tiered storage
features.According to Tobias Ford, chief technology officer of USi, in a
presentation to Storage Decisions attendees this week, the company
previously found EMC storage too costly and had a support issue
with Network Appliance Inc. (NetApp) two years ago that soured them
on the company.
"EMC locked in prices and we couldn't negotiate on a regular
basis, so costs weren't in line with the market after we had owned
the [EMC Symmetrix] frame for awhile," Ford said.
In 2004, USi inherited NetApp storage with an acquisition and liked
the snapshot capabilities that came with the filers. However, Ford
said, when the company's systems began to fill up in early 2005 and
performance issues arose, he was unhappy with the support from
NetApp.
"We had an outage, and we ended up paying back our clients
because we violated service level agreements (SLA). NetApp took a
week to give us a 'fix' of two new filers," he said. He advised
attendees to consult with user references about a vendor's "support
while you're under fire" before purchasing.
Though the company still has 200 terabytes (TB) each on EMC and
NetApp storage on the floor, Ford said the company plans to migrate
everything to 3PAR InServ Storage Server systems. USi purchased
four arrays from 3PAR, two S800s and two S400, which together have
a capacity of another 200 TB.
Thanks to thin provisioning, which helps control storage costs
by deferring disk purchases, and 3PAR's back-end storage
virtualisation, the company has been able to lower its prices and
remain in business alongside ultra-cheap Web-based hosting
services, such as Amason's S3.
"With our previous systems we were priced at $7 to $8 per
gigabyte per month -- Amazon's charging 10 cents per gigabyte per
month," Ford said. Adding the 3PAR system has allowed USi to lower
its base pricing to $2.50 per gigabyte per month, more in line with
market cost.
The company has converted some network-attached storage (NA)
shares into LUNs on the new storage area network (SAN) and said
customers have seen as much as a 50% performance improvement. The
company can migrate data frequently and easily between three tiers
of storage, consisting of 146 GB Fibre Channel drives in RAID-1 for
Tier-1, in a RAID-5 configuration for Tier-2 and 500 GB SATA drives
in a RAID-5 configuration for Tier-3.
Wish list: Snapshot features and automated migration
Still, in an environment that depends heavily on snapshots for
backup, tiered storage migration and testing, Ford said he's still
waiting to see 3PAR work out a few kinks.
Chief among them is the fact that 3PAR Recovery Manager for
Exchange, a software product extension to 3PAR's Virtual Copy
snapshot software specifically for snapshot images of Microsoft
Exchange databases, struggles to synchronise his large Exchange
mail stores, which can often run to 40,000-to-50,000 mailboxes at 1
GB to 2 GB each.
Snapshots will capture archive logs from the Exchange server,
which Ford said is useful for getting back to particular points in
time for restoring parts of the system. However, in a total outage
or disaster recovery scenario, without being able to take a full
snapshot of the mail store, the company won't be able to recover
the whole system.
For now, Ford said the company is "suffering" with Symantec's
NetBackup and tape, "and regularly blowing out the backup
windows."
He admitted his Exchange capacity is unusual, but also said 3PAR
has promised it is working on tighter integration with Microsoft's
Visual SourceSafe (VSS). Meanwhile, Ford said he is looking to
backing up email using a Microsoft tool, Data Protection Manager
(DPM) 2.0, in order to cut out integration issues entirely.
According to Craig Nunes, vice president of marketing for 3PAR
in an email to SearchStorage.com, "The testing [of this product]
with [USi's] specific server stack combination has not yet been
completed."
Another place where Ford said he'd like to see further
development in 3PAR's snapshot software is the fact that on
thin-provisioned volumes, it requires snapshots to be taken to the
same tier of storage and then migrated manually to a lower tier. On
baseline volumes, Ford said, snaps can be taken directly to a lower
tier of storage. It's another thing he said 3PAR has promised in a
future release.
"We support this capability today with one of our other Thin
Copy technologies, 3PAR Remote Copy, and expect to do the same with
3PAR Virtual Copy," according to Nunes.
Ultimately, Ford said he'd like to see 3PAR do away with manual
tiered storage migrations altogether by adding a feature like
Compellent Technologies Inc.'s Data Progression, which migrates
blocks automatically between tiers of disk according to frequency
of access.
"We tested Compellent very vigorously, but we just couldn't get
their array to perform well enough for our needs," Ford said. "If
they could, I'd still buy them -- I'd find a niche for them in my
environment."
According to Nunes, "this is a valuable technology and a part of
[3PAR's] statement of direction."
Finally, Ford said thin provisioning is also not a perfected
science. "You still absolutely must do careful capacity planning in
order to make it work," he said. "Some applications also aren't
compatible with thin provisioning because they will write data to
an entire allocated volume." Others can be made to work, but it
often takes training and testing with application
administrators.
"It's like Wac-A-Mole," Ford said. "You solve one problem, then
you move on to the next pain."