I've a monitoring tool named Spectrum from CA Click. It automatically forms links between devices by check their configuration, and etc. Recently a change was made on my switch by a regional and the links between the switch and router disapeared on the monitoring tool. I suspect this happened because of the "no ip address" command-line on the switch port g1/0/12, that it should have the ip address configured. My doubt is the relation or impact of configuring the IP address xxx.xxx.43.58 on the switch port g0/0. Thank you, in advance.

The actual configuration is below:

My coreswitch xxx.xxx.43.58:

xxxxxCORERS001#sh run int G1/0/12 
Building configuration...

Current configuration : 183 bytes
interface GigabitEthernet1/0/12
 description xxxxxWANXRT001 :: xxx.xxx.43.57::
 no switchport 
 no ip address
 ip ospf network point-to-point

My router xxx.xxx.43.57:

xxxxxWANXRT001#sh run int g0/0
Building configuration...

Current configuration : 285 bytes
interface GigabitEthernet0/0
 description UPLINK SWITCH-L3 xxxxxCORERS001 :: xxx.xxx.43.58::
 bandwidth 1000000
 ip address xxx.xxx.43.57
 ip wccp 62 redirect in
 ip ospf network point-to-point
 media-type sfp
 service-policy output LAN_QOS

no switchport removes a port from L2 switching to become a "routed port". That port can only be used for L3 communication, ie. routing. A VLAN defined on that port is a subinterface without MAC-based forwarding to other ports using the same VLAN ID.

no ip address removes an IP binding/L3 instance present on a port. It is normally used when configuring an interface for L2 where an IP address is usually assigned to the SVI (VLAN).

In combination, these commands effectively stop all forwarding and L3 communication on that port.

You'll need to ask the one who made these changes for the reason behind.

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