Product Reviews

Server mirroring and file replication are fault-tolerant features normally beyond the means of most small businesses, but the Non Stop Server from London Computer Centre (LCC) aims to provides just these facilities at an affordable price. The package is built around the SafeKit software from Evidian. LCC offers the Lite version, which provides server mirroring and file replication but loses the load-balancing feature of the full version.

The server comes pre-installed with SafeKit so all you need to do is load the software on the server you want protected - the price includes on-site assistance if you need it. Hardware-wise, the LCC server looks a beast but only offers a modest specification for the price, which includes a PC motherboard. Even so, during testing we used it to mirror a 1.13GHz Pentium III server running Windows 2000 Server and SQL Server and found it was up to the job.

Installation time will depend on the number of applications running on the primary server, as they all have to be loaded onto the secondary server. The servers don't need to be perfect duplicates, but they must be running the same applications, and the directories to be replicated must reside in the same locations. SafeKit is then installed on the designated primary server along with the latest Java Runtime Environment. Next, you modify the supplied user-configuration file with the IP

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addresses of the primary and secondary servers, add a virtual IP address to allow users to connect to the applications and the location of the directory to be replicated. For the latter, you can add multiple entries.

The Java-based SafeMonitor console is used to access all Non Stop Servers and provides three tabbed folders for remotely monitoring, controlling and configuring each system. The Monitor tab offers a simple colour-coded graphic for server status so you can see at a glance if there's a problem. Remote access is good too, as the SafeKit services can be stopped and started from here, while configuration files may be downloaded, modified and copied back to each server. However, alerting facilities are minimal. You only get an SNMP MIB file so you'll need a suitable network-management product to use any traps to generate broadcast, email or pager-based warnings.

Network utilisation was found to be extremely low too. Testing was conducted across a standard copper Gigabit Ethernet network, and data gathered from a network analyser found the two servers were using so little bandwidth they barely registered on the monitors. This is no doubt aided by the fact that all synchronisation data is compressed before being sent between the servers.

The reaction to a failure was virtually instantaneous. SafeMonitor observed us disconnecting the secondary server from the network and changed its status immediately to reflect this. With the connection back up, SafeKit automatically re-established contact and restored the mirror back to operational status. File replication was also impressive - changes made to the databases on the primary server were mirrored swiftly onto the secondary system.

The Non Stop Server delivers good fault-tolerant features to mission-critical systems and the low price makes it an option for small to medium-sized businesses. The lack of alerting tools is a downside, but otherwise we found the software easy to work with.