Replacing a NIC will show the old NIC mac address also in the server manager table. i.e. in my situation NIC representing eth0 was replaced by another NIC. But in the server maager table of UI it shows still eth0 as the old NIC and the newly added NIC is represented by eth3. But since the bonding involved eth0 and eth2, I was not able to communicate with the server. The screenshot of the server manager table which explains this issue clearly is attached.

If a NIC is removed, then one cannot login to the platform. For the right password also it says invalid password. I can login through ssh and through the console on the first server.