cisco Nexus 3172T - Loops detected in the network for mac

[Hafiz_HR]

Hi all,

I need help on this current log that we are received.

Basically we tried to create 2 Interfaces with a xx port-channel for VM migration purpose. also we tie this PO with vPC (not sure it is related to vPC or not).

then suddenly we have this kinds of log.

2023 Sep 26 13:04:05 jnixxx %FWM-2-STM_LOOP_DETECT: Loops detected in the network for mac 00xx.xxa7.3xx among ports Poxx and Poxx on vlan xxx - Disabling dynamic learning notifications for a period between xxx and xxx seconds on vlan xxx

Please advise.

[MHM Cisco World]

Do you config lacp as active or you run ON mode ?

[Hafiz_HR]

Hi,

we configured as active

[MHM Cisco World]

Are VM send lacp ? 

Can I see show etherchannel summary 

[Hafiz_HR]

Hi,

Basically the link that we are configured is between cisco nexus>dell powerswitch. So do I need configure as [active/passive] or [ON] mode for switches-to-switches? I understand that for VM we need to enable as active/passive as it is use LACP protocol. But we received as a request to configured as active not sure why, to me, enable as mode ON should be sufficient, am I wrong?

the network connection same like below illustration.

[VM]-------[Nexus 3172T]-------[DELL PowerSwitch S4148T]------[VM]

jnixxx# show port-channel summary
Flags:  D - Down        P - Up in port-channel (members)
        I - Individual  H - Hot-standby (LACP only)
        s - Suspended   r - Module-removed
        S - Switched    R - Routed
        U - Up (port-channel)
        M - Not in use. Min-links not met
--------------------------------------------------------------------------------
Group Port-       Type     Protocol  Member Ports
      Channel
--------------------------------------------------------------------------------
41    Po41(SU)    Eth      LACP      Eth1/49(P)   Eth1/50(P)
43    Po43(SU)    Eth      NONE      Eth1/43(P)   Eth1/44(P)
45    Po45(SU)    Eth      NONE      Eth1/45(P)   Eth1/46(P)   Eth1/47(P)
                                     Eth1/48(P)
48    Po48(SD)    Eth      LACP      Eth1/12(D)   Eth1/13(D)

 the migration port-channel should be PO48 with eth1/12-13. currently is not in-use.

Please advise.