IP
storage area network (SAN) vendor EqualLogic
Inc. has announced version 3.0 of its array software, which will
allow users new options provisioning storage in their
environments and allow for snapshots across volumes, tiered
storage automation and better performance monitoring. That's the
good news, say users, but some are also wondering when the
support for
serial attached SCSI (SAS) disks will come
about, something EqualLogic has promised for a while.
Currently, EqualLogic's iSCSI arrays, which come in "building
blocks" of varying capacities, automatically rebalance data when a
new member array is added to the environment -- this is similar to
products from other IP SAN startups, including LeftHand Networks
Inc., which operate much like a
NAS cluster but with block-level data
access. However, before version 3.0 of the software, any new
array added to a group would be automatically assimilated into
that group; whereas the new software allows administrators to
add arrays for specific storage pools, rather than load
balancing data across every array.
So, for example, if an administrator purchased a new EqualLogic
array and wanted to add that capacity only for engineering
applications within his company, he or she could block off the new
capacity as assigned to engineering only, and arrays holding data
for the sales or human resource departments would not load-balance
data across them.
Other new features in the software include volume collection,
which allows snapshots to be taken across volumes so that an
administrator can take a snapshot dedicated to one application,
such as email at the same time.
New tiered storage capabilities allow users to mix arrays with
different classes of drives into their storage pools, and migrate
data either automatically, according to frequency of access or
manually. EqualLogic is also announcing a new high-capacity array,
the PS400E, which uses new 750 GB
SATA drives from Seagate Technology. Another
array, the PS200X, which is to contain 10,000 RPM Seagate SATA
drives, was originally scheduled to be included in this week's
announcement but has been postponed until this fall, EqualLogic
said.
"We allow our customers options in everything, including whether
or not they want migration to happen automatically or manually,"
said John Joseph, vice president of marketing for EqualLogic, a
subtle shot at competitor Compellent, which recently announced
tiered storage automation -- and automation only -- for its
SANs.
Finally, new performance and capacity monitoring tools will
allow more visibility into the environment in order to keep up with
the new snapshot, tiered storage and pooling features, according to
EqualLogic.
The GUI interface allows managers to control all arrays and
pools from one group, but if a manager has more than one group in
several branch office locations, each group requires a separate
browser window for management.
According to Greg Schulz, founder and analyst with the StorageIO
Group, other restrictions still remaining on EqualLogic's products
have to do with the fact that the company has been strictly focused
on IP SANs, and they do not offer
Fibre Channel arrays or NAS boxes.
Still, Schulz said, "The best thing about this is that, like
every other EqualLogic software feature, they offer it to their
customers for free."
"The volume collections are what I'm most excited about," said
Alan Hunt, director of operations for Michigan regional law firm
Dickinson Wright PLLC, which currently has 11 arrays spread across
six sites. "This will allow me to create snapshot schedules at a
higher level, and it seems like it'll be a lot more logical as far
as the management goes."
Hunt also said he was enthused about tiered storage automation,
and that the new software will also give him "subtle clues" about
the best data protection scheme for each set of data. However, he
said, he's hoping that eventually EqualLogic will develop a
"semi-automatic" option for the tiered storage migration, one that
doesn't require him to either make every decision or make few
decisions for the migration between tiers.
Users still have a wish list
"I don't know that it will have a benefit for our environment,
as our biggest advantage using EqualLogic is striping data across
all arrays for better performance," said Steve Meckling, network
services administrator for Shiloh Industries Inc. "But it seems
like there were probably other customers who had a specific need
for this in different environments from ours."
Generally, Meckling said, he was still waiting for the solution
to a problem he had detailed in a previous SearchStorage.com story
(Factories pick monolithic IP SANs for
DR, March 28). "They allow for two-way replication
between arrays at different sites, yes," Meckling said. "But if
my last snapshot was sent over the wire at 2 a.m. and we have a
failure at 9 a.m., we can't just failback over immediately,
because the EqualLogic system knows that the data at the
secondary site might be 'stale.. I have argued that we should
have the ability to make the choice to lose some data if it's
important enough to get our server back up and running."
Hunt said that he would like EqualLogic to add the ability to
replicate one volume to multiple sites, something EqualLogic told
SearchStorage that it is working on adding in future releases. Hunt
also said that he would love to be able to manage all his groups in
one browser window, something EqualLogic also said will be
forthcoming.
"These are relatively minor issues," Hunt said. "But it would be
convenient."
The users also said they were also confused about EqualLogic's
earlier announcements that it was working on support for SAS disks.
EqualLogic first announced back in the fall of 2003 that it was
working with Maxtor to add support for the then-new disk type
within its arrays; recent announcements have reiterated this
commitment following Maxtor's acquisition by Seagate, which
EqualLogic also partners with.
"Generally, SCSI disk has a higher
mean time between failure (MTBF) than SATA,
at least in the perception of most storage buyers," Meckling
said. "I'm curious as to why it hasn't been added into the
arrays yet."
"Please stay tuned," Joseph said when asked for clarification on
EqualLogic's SAS roadmap. We have been public about our SAS
development plans but we are not providing any details at this
time."