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Value-for-money storage
iSCSI has matured into a disruptive technology and IP SAN
is its most interesting application. Anil Patrick R reports.
 Initially
dubbed the next generation storage protocol, iSCSI’s popularity
took a dive due to lack of vendor support. However, things seem
to be looking good with most storage majors now jumping on to the
IP SAN bandwagon.
The VFM factor
While startups were experimenting with IP SAN from the early days of iSCSI,
the rest of the storage industry waited to see how these organisations fared
before making an entry into this segment. This is why one of the first entrants
in the Indian IP SAN market was Intransa, about a year ago.
While the bigwigs of external storage preferred to wait and watch, products
like that of Intransa promoted the adoption of IP SANs in India. This prompted
most of the big names to venture into the segment. IP SANs are now being seen
as a value-for-money (VFM) option in your average storage vendor’s product
portfolio. On price/performance, IP SANs are generally held to outclass traditional
Fibre Channel SANs.
It is easy to understand the VFM nature of an IP SAN. It uses more affordable
technologies such as iSCSI and Gigabit Ethernet (GbE) vis-a-vis the expensive
FCP and optical fibre that a conventional SAN needs.
| The FC vs. IP routes |
| FC SAN |
IP SAN |
| Works on Fibre Channel link and uses FCP |
Works over TCP/IP and uses iSCSI over Gigabit Ethernet |
| Operates on a dedicated FC network |
Can work on internal LAN, but dedicated LAN is recommended |
| Proprietary technology inter-operability issues
might arise |
Uses open standards and freely available technology. Proprietary
nature might be limited only to controller or advanced tool
sets, and has very few known inter-operability issues |
| Expensive to implement, deploy and maintain |
Much lower implementation, deployment and maintenance costs
than FC SANs |
| Requires dedicated and experienced storage administrators
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Regular network administrators can be trained to handle an
IP SAN |
| Can operate at throughputs of up to 10 Gbps |
Can operate at a maximum throughput of less than 1 Gbps |
| Monolithic storage architecture |
Available in monolithic as well as separate controller plus
disk array architecture |
| Ideal for large enterprises and applications
that require high performance |
Ideal for SMBs and for low-cost backup or DR set-ups |
Time for a status check
According to Intransa, organisations have started looking at proper IP SANs
rather than just iSCSI-enabled storage boxes.
“From our viewpoint, IP SAN adoption is going very well
in the Indian enterprise. We have done more than 33 installations over the past
year,” says Vaidyanathan Iyer, Country Manager, Intransa. “Today,
customers are looking at IP SANs rather than iSCSI. This is a good sign, showing
that we have gone beyond the vendor evangelisation phase in India.”
Seen from NetApp’s perspective, things are going pretty well in the Indian
IP SAN market. “There has been a five-fold growth in IP SAN adoption when
we compare the first half of 2005 with the first half of 2004,” says Soumitra
Agarwal, Marketing Director, Network Appliance.
Adds Sanjay Kharade, Principal Consultant, Cisco Systems, India & SAARC:
“Banking & finance, telecom, manufacturing, IT/BPO and government are
some of the verticals that are witnessing a surge for adoption of storage networks.
Besides, the SMB market is realising the benefit of going SAN, and that is another
IP SAN market segment that is expected to boom.”
The driving factors
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Vendor promotion has been the biggest
factor behind this surge in IP SAN demand. The next reason is that lots
of enterprises are looking for a low-cost, low-investment proposition
for storage consolidation
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According to Agarwal, vendor promotion has been the biggest factor behind this
surge in IP SAN demand. The next reason is that lots of enterprises are looking
for a low-cost, low-investment proposition for storage consolidation.
With an IP SAN the entry barrier for storage consolidation is lowered, especially
for SMBs. This is because most of them do not have consolidated storage. These
organisations can start storage consolidation with an IP SAN. They are also
attractive for departmental offices and remote locations of organisations which
already have FC SANs at the core of their data centre. IP SANs have also being
considered for DR site deployments.
“Based on the IDC reports for the first half of calendar year 2005, my
estimate for the IP SAN market in India is roughly in the range of $4 million
to $4.5 million. The world-wide market for IP SANs is in the range of $250 million,”
informs Agarwal.
As per Intransa, the expected market for networked storage in 2005-06 is around
$150 million.
“Of this market, 3-4 percent will be taken up by IP SAN. We expect that
to reach 15 percent in about two years from now,” says Iyer.
| Inside an IP SAN |
| Most of the IP SANs available today
are essentially a combination of six cost-effective and high-performance
technologies, namely, iSCSI, Gigabit Ethernet (GbE) switches, Serial ATA
(SATA) hard disk arrays, Linux or similar open source OS kernel, virtual
LANs (VLAN), and Cat 6 cables.
A basic IP SAN consists
of GbE switches, a disk array controller, and a SATA disk RAID array.
Depending on the vendor's product design, the controller and hard disks
may be a single unit or separate elements. The merits and demerits of
these two arrangements in terms of scalability and flexibility are highly
debatable. Vendors whose products have separate controller and switch
units claim that it is easier to scale up with this arrangement.
The disk array controller
is connected via GbE switches to the drive arrays and servers using Cat
6 cables. These controllers are usually powered by applications that run
on an open source OS like Linux. This OS is suitably hardened for data
security.
While none of the components
by themselves (except for the controller) are exactly rocket science,
their right combination has done wonders in the form of an IP SAN.
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Hype vs. reality
Manish Bapat, Business Manager, NAS & CAS, EMC India, dismisses the reports
of IP SAN’s popularity as premature. “Although the IP SAN market is
picking up, a lot of it is more hype than reality. The adoption is over a small
base, so it is too early to say whether it is actually picking up. When compared
to the overall market, it is still a small figure.” According to Bapat,
people are opting for IP SANs in non-critical applications where parameters
like performance and response times are not important. “Now these organisations
have a choice. From our (EMC) perspective, it is more about heterogeneous environments
(comprising NAS, iSCSI SAN boxes, etc.), and about end-customers with cost limitations,”
he adds.
These factors notwithstanding, the growing popularity of
IP SANs cannot be denied. The year 2005-06 is witnessing a good rate of IP SAN
adoption. This is bound to increase in the coming years.
"From our viewpoint, IP SAN adoption is going very well in the
Indian enterprise. We have done more than 33 installations over the
past year"
- Vaidyanathan Iyer
Country Manager
Intransa
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"There has been a five-fold growth in IP SAN adoption when we
compare the first half of 2005 with the first half of 2004"
- Soumitra Agarwal
Marketing Director
Network Appliance
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"The IP SAN market is picking up, but a lot of it is more hype
than reality. The adoption is over a small base"
- Manish Bapat
Business Manager, NAS & CAS
EMC India
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10 GbE IP SANs—not quite ready yet
One of most awaited IP SAN advances has been running them on 10 Gigabit Ethernet.
While the technology is already out, vendor support is lacking, which brings
in issues like cost and non-availability of equipment.
Vendors such as Intransa have already demonstrated IP SANs running on 10 GbE.
That said, it will be a while before it actually goes into production. “Technology
support on the equipment front from vendors is yet to mature for 10 GbE to take
off. We expect 10 GbE IP SANs to go mainstream by mid-2006,” says Iyer.
anilpatrick@networkmagazineindia.com
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