COMSTAR credit union conquers e-mail availability issues with real-time WAN-based data replication solution

Computer Technology Review, June-July, 2005 by Gil Rapaport

Established in 1933, COMSTAR Federal Credit Union provides a wide array of banking services to over 20,000 members residing primarily in the Washington, DC, metro area. The credit union's underlying philosophy is to focus on member convenience and satisfaction, growth, organizational excellence and success. As part of its constant aspiration to serve its members more efficiently and effectively, COMSTAR is always on the lookout for innovative technology, especially technology that can help ensure the uptime of its critical information systems.

As e-mail has become a crucial element in the way COMSTAR interacts with its members, the credit union's IT personnel were charged with the task of choosing and deploying a solution that would maintain the constant availability of its Microsoft Exchange server infrastructure.

"Communicating with our customers via e-mail is critical to the success of our business today," said Stephen Jones, vice president of information systems at COMSTAR. "When a customer sends a request or an inquiry through e-mail, we need to be 100 percent certain that we receive that e-mail. We needed a solution to facilitate real-time replication of the Information Store for our Microsoft Exchange servers. As a financial institution, COMSTAR is in a unique situation in that data may literally equal money and certain data simply must not be lost.

"We decided that the time it takes to restore backups from disk or tape and the potential for losing messages sent since our most recent backup would have an adverse impact on our members. We needed to investigate technologies that would enable immediate switchover in case of server failure. We also hoped to locate a solution that would offer stability and WAN-based replication to our co-location site that would allow us to throttle bandwidth."

Jones began his search and came across an independent review that tested four high-availability products for Microsoft's Exchange Server. The test included: Fujitsu/Softek's Softek Replicator 2.1.2; LeftHand Networks' SAN/iQ Software; Remote IP Copy Software and NSM 200 SAN Module combination; NSI Software's Double-Take for Windows 4.3; and Xosoft's WANSyncHA Exchange 3.5.2 Build 45. The winner in this review was XOsoft's WANSyncHA, which did not drop any messages during failover. Since that was Jones' primary objective, he looked into WANSyncHA along with a few other major players in the market.

COMSTAR found the ideal combination of reasonable cost and performance in XOsoft's WANSyncHA Exchange. "WANSyncHA's Exchange-aware, high-performance replication was the key deciding factor, but we also found the simplicity with which it would complement our existing disaster recovery infrastructure highly appealing".

WANSyncHA Provides Uninterrupted Exchange Server Availability

Jones and his team built two Qsol servers with ICP Vortex disk controllers configured for RAID 5 and transferred the Exchange Information Store to them. Once WANSyncHA Exchange was installed on both master and replica servers, they proceeded to thoroughly test the product. Testing included numerous complete restores of the Information Store between the two servers, as well as switchovers using WANSyncHA's High Availability feature. The final WANSyncHA Exchange deployment now continuously replicates the Exchange Information Store from COMSTAR's primary server to the credit union's colocation site over WAN, in real time.

WANSyncHA Delivers

"WANSyncHA Exchange has proven extremely easy to deploy. It required neither server reboots nor Exchange client shutdowns. The level of support we received from XOsoft was outstanding and factored heavily in our decision to use WANSyncHA," said Jones. "We also appreciate the added cost-efficiency afforded by the fact that no additional Microsoft Exchange server licenses need be acquired to implement this solution. We have achieved great peace of mind, knowing that WANSyncHA will significantly decrease potential downtime in case of a disaster and that little or no information will be lost in the process. Following our positive experience with WANSyncHA Exchange, we implemented additional WANSync solutions--WANSync Server for our duplicate NAS servers and WANSyncCD for safe and accurate distribution of our internal and external Web content."

Data Availability Over WAN

The WANSyncHA solution chosen by the COMSTAR is an advanced WAN-based application availability software platform. WANSyncHA maintains identical replicas of complete application servers through continuous real-time replication and provides peerless, high application availability with application-aware automatic failover over LAN and WAN in case of disaster. Should a server fail or have to be shut down for maintenance, either a local or a geographically remote WANSyncHA replica can instantaneously and automatically take its place to provide the fastest path to recovery.

The Complete Solution

Jones knows what he's doing when it comes to protecting his company's data. Prior to implementing WANSyncHA, Jones deployed Adonis DNS Appliances from BlueCat Networks in order to isolate the IP addresses provided for their critical servers at co-locations by having them correspond to the name server at each physical location. That, coupled with short TTL's for each record, enables COMSTAR to have a seamless failover from one location to the other in the event one of their Internet connections should fail. Their name server, using the Internet connection that is down, will simply be unavailable and is thus unable to distribute the addresses on the subnet that are affected by the outage. This leaves the name server at their co-location to answer all queries with the address set that is currently available and if both connections are working, it load-balances between locations using the round-robin method.