DNA Center CMIC and Management Port Subents

[pinglis]

The DNA Center Installation guide states the follow with respect to the subnets used for the various ports:

“Ensure that the addresses and their corresponding subnets do not overlap. Service communication issues can result if they do.”

Does this restriction apply to the management port and CMIC port or can these be on the same subnet?

[Mike.Cifelli]

Does this restriction apply to the management port and CMIC port or can these be on the same subnet?

-This is actually a good question.  I know that for any interface that the maglev wizard is aware of you cannot have overlapping subnets as you mentioned (ie - management/enterprise).  My assumption is that you can have CIMC and 1 maglev configured interface in same subnet since IMO maglev is unaware of CIMC, but again to be honest I am not sure.  Do note that you cannot change the cluster link after installation.  If you attempt to maglev will throw an error and if you need to change it you will have to reimage/re-install.  HTH!

[pinglis]

Actually my question came about because I looking at taking over a new DNA Center set up by a supplier and it looks like they've messed up the basic settings (they set cluster/container subnets to be supernets including all our live LAN subnets) and so it looks like we will need to re-image it. I am trying to make sure I get everything clear before we start.

In the current setup the CMIC and Enterprise ports are in the same subnet (management port not enabled) so you could be right about it only applying to what maglev is aware of.

[rasmus.elmholt]

The overlap is only a problem of the interfaces maglev know of and not the CIMC port.

You can have the CIMC port in the same subnet as the enterprise port.

Be aware that in the latest versions of DNAC it want access to the CIMC from the enterprise port for monitoring. And the IPs should be reachable from each other.

[Mike.Cifelli]

As an FYSA for the cluster/container subnets Cisco actually recommends using the defaults, which are:

Container Subnet field: 169.254.32.0/20

Cluster Subnet field: 169.254.48.0/20

See the following: Cisco DNA Center Second-Generation Appliance Installation Guide, Release 2.1.2 - Configure the Appliance Using the Maglev Wizard [Cisco DNA Center] - Cisco