the servers are loadbalancing between the switches '3'
and '2' and the link between the two switches is blocked.
This link was forwarding before and thus any traffic going to the server was
send to the Servers correctly no matter on which switch they are active.
However after addition of another link in between the switches 'root'
and '1', the path cost to the root has decreased and thus the link
between the '2' and '3' is Blocking and the other link between
the '2' and '1' is Forwarding as it should be ideally. But
this would be creating an issue because the trafic coming from outside i.e.
through switch '1' to the server will be correctly send to the
server if the server NIC is active on the '3' because the Virtual MAC
addresses are binded accordinlgy. In case the server falls onto the other
NIC which is on the '2' the traffic won't be able to pass because the
MAC address is not binded on the trunk connecting the switches '1'
and '2'. This binding cannot be done because the same MAC address is
being learned on the another trunk on the '1' which is connecting
to 'root'. So if we bind the same Virtual MAC on two trunks on the same
switch ('1') then this will cause MAC Address Flapping on the
switch and hence canot be done.
In another case,we can able to bind virtuak MAC on two trunks on the same
switch('1') and it's working fine.
The servers are load balancing in round robin fashion. each server has 2 NICs and work in Active-Passive mode. The servers load balance each other when all their active links are connected to '3' switch but when two of the active NICs of two servers are connected to '3' and the rest of the two active NICs from the other two servers are connected to '2' switch then only the forst 2 servers load balance and the other 2 servers do not load balance.
Thanks in advance.