Controller Network Redundancy
Voted best answer
You must remember that the two lines of redundant Control Net need to be two separate subnets, so having IP 172.16.1.1 with mask 255.255.240.0 will not allow any redundant adress in the same network, so no 172.16.1.3 and no 172.16.10.3 (these are addresses from the same subnet). You should input an address like the one mentioned above (172.17.1.1). If this is impossible remember any other, like 172.16.101.1, will be ok as long it will be from another subnet.
Hope this helps,
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