Failover pair over distance

Are you talking about the hardware failover port, or network failover using one of the TMM switchports?

The hardware failover port is just a voltage, and would not be something you can simply plug into a switch. It is limited to a 50-foot distance.

Network failover is a heartbeat sent via IP and can be treated as any other network traffic. Depending on network conditions you may need to tune the timeout value (default = 3 seconds)...but 3 seconds is, relatively speaking, a long time. Just consider your overall HA strategy.

More information is available in K2397.