TROUBLESHOOTING MERAKI MS390 SWITCH

[Sencyty]

I need urgent assistance, don't know what could be wrong. I work remotely, just noticed this morning that one of my access switch (MS390) has been completely offline since Friday night. I check the uplink connection with Nexus 9k every thing looks good and up. The connection was on vlan 250 as trunk port on 9k, but on MS390 this morning it was showing vlan1. My boss suggested reboot after which the MS not up but now appear to be on vlan128 against the vlan250 as connected on 9k. I am thinking of going to the site but I truly don't know what could be the problem, am feeling it could be layer1 issue or hardware problem. I need you guys to help out ASAP please.

Thank you.

[Georg Pauwen]

Hello,

tough one...especially the Vlan change. What exactly do you mean by:

--> The connection was on vlan 250 as trunk port on 9k

[Sencyty]

thats connection of the ms390 interface from layer3 switch. the trunk interface

[Sencyty]

Hey guys i got this resolved but still want to know what could be the problem. the previous command was as below

switchport mode trunk

switchport trunk native vlan 250

no shutdown.

i just added

switchport trunk allowed vlan 250 and the interface comes up

can anyone clarify this please.

[Georg Pauwen · Accepted solution]

Hello,

I looked at the configration example linked below, and it appears that the native Vlan needs to be in the allowed Vlan list:

https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus9000/sw/7-x/interfaces/configuration/guide/b_Cisco_Nexus_9000_Series_NX-OS_Interfaces_Configuration_Guide_7x/b_Cisco_Nexus_9000_Series_NX-OS_Interfaces_Configuration_Guide_7x_chapter_0100...