Coyote Point Equalizer balances loads with finesse
Simple and effective, the E350 is a good fit for the budget-conscious
The Coyote Point Equalizer E350 is a great example of a product that performs a basic function — load balancing — and does it well. Simpler than the other two appliances I tested, the E350 costs about 80 percent less.
A 1U, rack-mount box, the E350 is an excellent, fourth-generation version of a basic load balancer. With a $5,995 list price, it has a relatively compact feature set, but it is also quite simple to set up and deploy, can create a load-balanced cluster with the persistent connections required for e-commerce, and has options for SSL acceleration and global/geographic load balancing as well.
The E350 supports both layer 4 and layer 7 clusters. In other words, it can create a cluster where requests are distributed to all the servers or a cluster where requests are distributed depending on their content, so that certain URLs or file types can come from one set of servers, while everything else comes from a different set.
Setting up the clusters is straightforward, and the manual -- provided in hard copy and online -- nicely explains the few options. The initial network configuration is done via a serial terminal; the rest of the configuration is done via Web browser.
The appliance supports the usual load-balancing algorithms, including least connections, fastest response, adaptive and round robin, as well as an agent-based algorithm that is accurate if the agent is run on each server.
The E350 supports connection persistence using cookies, inserting them in the HTTP returned to the client. This approach ensures that the client will return to the same server in the cluster, if desired, for transactions. The E350 checks servers to ensure that they are operational and verifies that content is available.
The E350 supports an active/passive fail-over model and transfers all session data to the backup device so that individual client sessions are maintained even if the primary Equalizer fails. The Equalizer is also available with the Xcel, an optional SSL acceleration card.
Although the E350 provides basic functions rather than the wide array of acceleration capabilities, its low price and ease of use make it worthy of consideration in organizations that want to add fault tolerance and scalability to their Web sites.