One of the largest self-storage companies in the US has
taken an unorthodox approach to managing its data centres since
last year. In an effort to get business decision-makers at the
company closer to its retail outlets in the field, the company
decentralised its data centres and its data, returning some of its
storage area network (SAN) data to
direct-attached storage (DAS), outsourced its backup and used
WAFS from
Riverbed to tie it all together.
The company moved from a centralised data centre in Cleveland, in
which it managed 2 terabytes (TB) of data on an HP MSA 1000 SAN,
including a clustered Exchange server, to five main offices divided
by region. The company now has dispersed headquarters in Cleveland
and Pennsylvania. Pennsylvania is the the primary data site, and
Cleveland is the disaster recovery site. Roughly 1 TB of its SAN
data has been returned to DAS on HP ProLiant servers, and the
Exchange server has also been returned to DAS, in contrast to
industry trends over the last few years.
"With the Exchange server, it was all about simplifying
management," said CIO Ajai Nair, who was brought on eight months
ago to oversee the project. "I found that managing the cluster
introduced more variables into diagnosing a problem if the system
went down, and that wasn't outweighed by the benefits." The
Exchange environment had been on a high availability pair of HP
ProLiants attached to the MSA, and the data was migrated to a
newer, single ProLiant with internal disk. The company's SQL server
was also migrated back to its own DAS.
The MSA, however, remains in place -- serving files. The company
decided to consolidate five file servers into one more powerful
Windows host, and the MSA was the only device with enough storage
space to accommodate all the data.
"It was a conscious decision," Nair said of moving the database
off the SAN. The SQL server is running a financial application,
Great Plains, which is tied in to the company's Sarbanes-Oxley
(SOX) compliance. The company plans to upgrade from version 8 to
version 10 of Great Plains soon, and SOX dictates extensive testing
when upgrading such applications. Nair said the easiest way to
perform this testing is to build an entirely new environment, which
is cheaper and simpler to do with DAS.
To get all this accomplished, the company also used an
unorthodox method of data migration. During an earlier phase of the
restructuring process, U-Store-It had outsourced its backup to IPR
International LLC's DataGuardian software-as-a-service (SaaS).
Previously, U-Store-It had been doing traditional daily incremental
and weekly full tape backups. "If we were a normal organisation of
the same size rather than a 24x7 business, tape backups might still
have worked," Nair said. "But, the backup window left us some
exposure, and if it failed, we'd have to send someone in the middle
of the night on a weekend to fix it." In the course of its data
migration project, it enlisted IPR's help to transfer the data.
"It's got a Web-based interface, so we could just restore a file or
data set to wherever we pointed [the service] to."
With its file servers consolidated and its Exchange server
removed from networked storage, all while serving newly distributed
offices, WAN latency between offices was sure to be an issue.
Putting servers in each office was also not an option for Nair.
"I've been in that situation [of servers and backup at
distributed offices] before," he said. "Management is horrible,
backup doesn't get done, patches are inconsistent… I wasn't going
back to that."
Instead, Nair put in several wide area file services (WAFS)
appliances from Riverbed, which he had also previously used with
another employer. The Pennsylvania office for U-Store-It is running
a Riverbed Steelhead 2020, the Cleveland office has a Steelhead
1010 on standby for disaster recovery purposes, and the rest of the
company's smaller offices are running the Steelhead 100
appliances.
U-Store-It, a Cisco networking shop, also considered the router
giant's Wide Area Application Services (WAAS) product, but Nair
said its GUI was less intuitive than Riverbed's for his taste, and
he preferred the fact that Riverbed sits inline between the router
and the network switch, while Cisco's WAAS remains outside that
connection, passing back traffic it can't optimise. "My preference
is to have data pass once through the network," he said. (Cisco's
Wide Area Application Engine (WAE) can be configured to sit between
the router and switch, but requires a WAE Inline Network Adapter
according to
Cisco's documentation. WAAS can also be
integrated with the router itself, tagging certain traffic to
bypass the WAAS module.)
So far, he said, the Riverbed product has worked well,
especially when it comes to Exchange, since the Steelhead
appliances perform Exchange spoofing -- caching emails on the local
box for download when users log on to the system again. "It's a
really nice feature that we hadn't even thought about," Nair
said.
One feature the company has thought about for Riverbed to add,
however, is the ability to act as a dynamic host configuration
protocol (DHCP) server, which assigns IP addresses to hosts on the
fly, something WAAS does. "It's not a core skill for Riverbed,"
Nair admitted. "But, since we don't have servers in the field, my
switches are providing DHCP, and I'd rather have them just being
switches."
Nair said he's aware that U-Store-It's approach has been off the
beaten path. But, he said, it was the only choice given the goals
of the business. He said he will probably consider moving back to
SAN for his SQL database at some point, but otherwise is happy with
how the process turned out. "It was great for us to do this, if
only for the purge process that happens whenever you move data,
when you ask yourself, 'do I really need this?'"