I'm trying to set up monitoring of my DMZ switch. All servers in this dmz are in a 172.18.x.x subnet, and all ports on the switch are in a VLAN51. This VLAN only exists on this switch and there is no trunking involved. The switch is a 3550-12T. I'm trying to reach the switch by creating a loopback interface with a 172.18.x.x address. I am unable to ping the switch from any of the servers that are in that subnet. If I do a show arp on the switch I don't see anything. Anybody have any ideas why I can't reach this switch via the loopback interface?
Do I have to give VLAN 1 an IP and try and get there that way?
I have all firewall rules in place properly as I can get to all servers that are on that switch, I just can't get to the switch.
Any ideas on how best to set this up.
Thanks very much,
Is there a reason why you want a loopback interface ?.
If you just want the switch to be layer 2 which you very probably do if it is a DMZ switch then shutdown vlan 1, create a vlan51 SVI, assign it an ip address out of the 172.18.x.x range and set the default-gateway to be the DMZ interface on your firewall.