Monitors in Link Controller

Hey Manthan

Is it used for Transparent Monitoring, which means you are monitoring the path to a device's where the device IP address and port is specified in the Alias Address and Alias Port.

For instance, you could create a Transparent Monitor to ping Google DNS 8.8.8.8. Here you would set the Alias address to 8.8.8.8 and this monitor will pass through your switches, routers and firewalls trying to reach 8.8.8.8. If it fails it will mark the monitor down. This is used for example a Gateway Pool where you have multiple ISPs. If the monitor fails it will choose the other ISP (pool member) in the Gateway Pool.

"A transparent health monitor forces the BIG-IP system to ping through a transparent network device with which it is associated (usually a firewall), to a destination device. This behavior allows the transparent device to be tested, and if there is no response from the destination device, the BIG-IP system marks the transparent device down."

Here is some more information about the concept:

K8971: Creating transparent ICMP health monitors

Manual Chapter: Monitors Concepts

I hope this helps! :)