Adaptec's little SAN that can
Snap Server 720i, an entry-level iSCSI
SAN, packs big features in a small format
Snap Server 720i was
selected for an InfoWorld Technology of the Year award.
Many different combinations of drives, controllers, and software are available
in storage arrays for small and midsize businesses, but one example that you
should not miss is theSnap Server 720ithat Adaptec trotted out last
720i, Adaptec proposes an affordable yet scalable iSCSI SAN module that doesn't
skimp on performance and is easy to manage. From my early test-drive, I can
attest that the 720i delivers on those promises, despite a minor hiccup or two.
compact 1U box comes with four SATA drives, a single power supply, and three
Gigabit Ethernet cards to connect to an iSCSI SAN and to your management
console. A choice of 250GB or 500GB drives puts total capacity at 1TB or 2TB,
but if you need more you can daisy-chain as many as eightAdaptec SANbloc S50 expansion modules, 2U
enclosures loaded with as many as12 SAS(serial attached SCSI) or SATA drives.
don't find many storage solutions in the SMB space that can expand so easily to
100 drives, making the720ian interesting proposition for small companies that expect their
capacity needs to grow significantly.
evaluation units I received from Adaptec had a nominal 2TB capacity, but using
RAID 5 with a hot spare drive leaves little more than 900GB available on each
one.SANbloc expansion moduleswill be needed if
that's not enough for you.
Adaptec controller inside the720isupports just about any RAID level,
including dual parity protection, which is a common-sense choice for large SATA
drives. Still, having only four drives in the array limits your choice to either
RAID 5 or mirroring, neither of which protects against a second drive failure
while recovering from the first one. However remote that possibility may be,
adding an expansion module to the 720i is a surefire remedy, because the
addition of more drives gives you more choices in RAID levels.
Another option is to get a second 720i
and mirror volumes across the two, so you can easily switch to the
second array if the first one goes south -- more on this later.
Setting up my two720iwas, yes indeed, a snap. I
connected the management port to my data subnet and the other two
GigE ports on the back of the unit to my SAN. Considering the 720i
has only one power supply, it's good that the onboard management
software can also monitor a UPS.
If you have used other products from
Adaptec, Storage Manager will look like an old friend. Regardless, it won't take
long to get acquainted with its GUI, from which you can centralize the
monitoring of all of your arrays. In addition to typical management tasks such
as setting up the network configuration and creating LUNs (logical unit
numbers), Storage Manager allows you to provision storage without even touching
your Windows machines.
After installing an agent on each of my
application servers, I was able to create and assign new volumes remotely from
the management console. Behind the scenes, the provisioning agent took care of
formatting the volume, assigning a drive letter and preparing the Microsoft
iSCSI initiator for the connection -- this last step is very helpful because it
avoids having to jump between consoles.
During my testing I ran into a couple of
network hiccups. For example, restarting after a sudden power off, the array
didn't respond to Storage Manager or to a ping. Nevertheless, the 720i's
powerful CLI, which you can access via telnet or serial port, came to the
The Adaptec CLI's comprehensive online
help -- which will even guide you word by word through a command -- puts most
similar tools to shame. I never needed to keep a reference manual close by to
type a command, and neither will you.
The720ifeature that takes the cake is
the built-in remote mirroring. Naturally, mirroring requires two
arrays but brings ironclad protection to critical volumes by
automatically creating remote mirrors of selected volumes on the
Remote mirroring is also very easy and
quick to implement; in fact, creating a mirror is faster than
explaining how it works. Here is how: From Storage Manager I clicked
on one of my application servers, chose the volume to protect, and
then clicked the appropriate entry from the pop-up menu. The wizard
proposed to create a new volume of the same size on the second
array, and I clicked Next and Apply to confirm. My mirror volume was
To mimic a real-life
scenario, before testing the fail-over, I added more
files to the source volume, then increased its size by
5GB. Peeking at the second array, I noticed that Storage
Manager had quietly increased the size of the mirror as
well -- so far, so good.
To simulate a failure, I simply pulled
the power cord from the 720i. In the time it took me to return to
the console, Storage Manager was showing that the array was down.
From my application server, I opened the "e;lost"e; volume in Windows
Explorer and all of my files, including the last batch, were still
there. The automatic fail-over was successful; the system had
automatically switched my server to the mirror volume.
I don't know if the power-off hiccups
I experienced were caused by the array or by some glitch on my
network, and frankly it doesn't matter much because sudden power
loss is an unlikely event in most installations. What counts more is
that theAdaptec Snap Server 720icombines
great scalability, reassuring high-availability features, and
excellent management tools, all at a very affordable price and with
a three-year warranty on hardware. Few arrays in its class can even
come close to that.