nothing more important for an online exchange than to
provide its customers 24x7 access, while sticking to
the rigid regulatory norms laid down by SEBI. Here's
how Refo-Sify implemented, reliable and scalable storage
solution. by Soutiman Dasgupta & Minu Sirsalewala
Securities India Private Limited has to adhere to a
rigid set of regulations to protect its customers. After
all a site that offers online and offline equity and
futures trading for retail customers needs to keep its
socks pulled up all the time. It's the customer's money
at stake. The company needed to offer 24x7 availability
to its customers, and stick to the regulatory norms
laid down by SEBI (Securities Exchange Board of India).
The norms require historical data to be continuously
available for a specific period. The key to make all
this happen was to get serious about data storage and
establish a fool-proof enterprise storage solution.
The solution needed to be reliable, redundant, scalable,
allow for easy backup and recovery, and provide business
continuity. After evaluating several data storage vendors,
Manoj Chandiramani, Assistant Vice President, Networks,
decided to use storage systems from Compaq and Sun.
Solutions from the two vendors co-exist in harmony and
provide real-time storage with facilities for backup
Refco-Sify Securities Private Ltd, offers online
equity and futures trading for retail clients,
as well as execution and clearing services for
financial institutions. The company started
its online operations in August 2001. It is
linked to the NSE (National Stock Exchange)
and BSE (Bombay Stock Exchange) through VSAT
links and leased lines.
The company needed a robust, reliable and scalable
enterprise storage solution that integrated
well with its existing backend architecture,
at the same time preserving seven years of historical
data, as stipulated by SEBI.
The company opted for a mix of enterprise storage
solutions from Compaq and Sun. It uses two StorageWorks
RA4100 boxes and 16 rack-mounted 6400R ProLiant
servers from Compaq and ten 500 and 220R servers
The online transaction system can log in 500
simultaneous users and execute each request
in less than a second with the additional facility
for managing excess load. In case all the servers
in the cluster fail simultaneously, the data
can be recovered within 45 minutes.
NEED TO STORE
An online exchange should allow throughput in high-volumes
and have little room for downtime. The solution has
to be robust, reliable, and integrate well with the
backend architecture. Since Refco-Sify decided to use
Oracle 8i as the database, the storage needed to support
the related applications as well.
"We decided not to use a server-based storage solution
because you have to keep adding disks to the server
as data volumes increase and it is not fool-proof. A
cluster lets the system automatically switchover in
case of disk failure. One can 'hot-swap' disks without
interrupting operations and still maintain integrity
of the data. You can also create a logical partition
in the same physical storage," pointed out Manoj.
Refco-Sify prefers to use a mix of solutions from Compaq
and Sun. It uses Compaq's PL 5500R servers, PL 6400R
servers, ML 330 servers, DL 380R servers, RAID Array
4100 storage boxes, fiber switches, ProLiant servers
and Compaq PCs. And it uses Sun's E3500 servers, 220R
servers, 250R servers, Array 1000 storage boxes, Array
5000 storage boxes, and UltraSparc servers. The storage
applications are managed by Compaq StorageWorks Command
Console and Microsoft Cluster Server software on Compaq
boxes. Sun's boxes run proprietary storage software.
There is a logical partition on each storage box to
The online exchange site uses e-commerce solutions from
BroadVision. A proprietary order routing application
called RORS is used to route orders to the stock exchanges.
The Compaq hardware runs Windows NT 4.0 Server as the
NOS (Network Operating System) and the Sun hardware
uses Solaris. The Oracle 8i database is run along with
Oracle Fail Safe and Oracle Parallel Server. Oracle
Fail Safe works with Microsoft Cluster Server to restart
Oracle databases and applications on a surviving cluster
node in the event of a system failure. And Oracle Parallel
Server allows multiple instances to access a shared
The company used products from two different hardware
vendors and two different NOSs to take advantage of
the features offered by both. "We could have used
Solaris on an Intel platform loaded on a Compaq box
to give us the features of Solaris. But we wanted to
use Sun's iPlanet as a Web server because it is a stable
and strong product," said Manoj.
The storage boxes operate at RAID Level 5 and the network
is designed to suit different configurations. This will
help add servers and storage capacity in future. One
can transform the existing storage configuration into
a SAN (Storage Area Network) which will run on both
NT and Solaris. The SAN can create a common pool of
storage for the entire network.
The Build Up
A team of vendors and solution providers helped implement
the network. Despite the herculean task of managing
and coordinating the delivery schedules of the different
vendors and consultants, the entire solution was up
and running in 75 days. "We tested the performance
of the system and discovered that it can login 500 simultaneous
users and execute each request in less than a second.
In case of a surge in data traffic during peak hours,
I can add hardware to support the load," said Manoj.
Security solutions have been provided by Checkpoint.
The applications run on Cisco hardware which is placed
at the gateway level. This forbids unwanted access and
data to be eliminated at the entry level.
BACKUP AND RECOVERY
Regulatory norms stipulate that transaction details
should be available to clients for 90 days. SEBI may
want to access a year's data anytime. And Refco-Sify
has to preserve historical data for seven years. This
means there should be adequate backup and recovery mechanisms
to complement data storage.
The company uses Compaq StorageWorks 40/80 and 35/70
and DLT drives from HP for its backup needs. Two sets
of backup are maintained at the main office in Mumbai
and at another remote location. "The remote location
lies in a separate seismic zone," said Manoj. Backup
is taken everyday at midnight since this is when traffic
is the least and there is minimum downtime.
Recovery of data is facilitated by the use of server
clusters. The advantage of a cluster solution is that
if one server fails the others can take over automatically.
If a hard drive in a server fails, it can be replaced
with a new one, without the box going down. "In
the worst case, if all the clusters fail the site can
be up and data can be recovered in 45 minutes by tweaking
the system," said Manoj.
DOWN THE ROAD
In future Refco-Sify wants to convert its enterprise
storage solution into a SAN. "All I have to do
is add a small component to the Compaq box to make it
function in a SAN," said Manoj. This way, the company
can offer additional services to its clients. And data
stored at the site can be secure since it is inside
the company's network and backups can be taken as usual.
Currently, each storage box has a logical partition
which allows the other partition in the same box to
take over in case of failure. But what happens if the
entire box fails? With more boxes in the network, a
separate server can act as the fail-over.
"We would like to use robotic arms for our backup
operations. Loading each DLT drive can be a painful
task. You need to have a person there all the time.
Automating the process can save time and manpower,"