nexus 3000 vlan

iceisfun

Member
Jul 19, 2014
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4
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I'm having some trouble with a nexus 3k and vlan configuration. This is the first cisco device I've touched in many years and normally use Arista and Ubiquiti switches.

This seems like it should be pretty simple, there are a few hypervisors and storage boxes with lacp 40gbit redundant interfaces.

All ports on the switch are switchport mode trunk, switchport trunk allowed vlan all and vlans 1-255 are defined.
Trunk port 1/64 is qsfp to Arista trunk port configured the same way, same vlans defined, allowed, etc.

I have two problems

I can't get traffic going out from a server into the switch to leave the switch untagged/native, I do see inbound untagged traffic getting to my test server trunk interface.

I tried to resolve this by removing vlan native from our entire network putting that traffic into vlan 10, this works great everywhere I tested (Arista and other non cisco switches)

The other issue I have is I can't get traffic from some vlans, such as 10 to work from the test server, some do work like server management vlans over the trunk lacp interface.

When moving the server from the 40g cisco port to a 40g arista port it all works perfect, and traffic on the local cisco switch seems to work.

What have I missed about the vlan setup on these cisco switches when working with other switches?
 

Discountsocks

New Member
Aug 16, 2018
8
7
3
Can you give a diagram and or interface configuration where you are seeing the issue (preferably the server port as well as the uplink)? I might be misreading your description, but it seems unclear to me when you are saying that you "can't get traffic going out from a server into the switch to leave the switch untagged/native" but that you "see inbound untagged traffic getting to my test server trunk interface"?
 

iceisfun

Member
Jul 19, 2014
30
4
8
If I unplug this windows server from the Nexus and move it one step up the chain to the Arista 40gb switch everything works perfect, also other things plugged into the Nexus seem to be able to talk just fine.



Windows Server 2016 HyperV
With VM setup interface 0: untagged, interface 1: access v.99
With OS management sub interface on v.100

Connected to (switchport mode trunk)

Nexus 3000 qsfp 40gb

Connected to (switchport mode trunk on both sides)

Arista qsfp 40gb

Connected to (QSFP 40GB single channel channelgroup trunk to 4 channel 10GB SFP+ channelgroup trunk)

Arista sfp+ 10gb

Connected to (SFP+, SFP+ to SFP+, SFP+ all switchport mode trunk, spanning tree two paths)

Ubiquiti ES48

Connected to untagged device 1gb
 
Last edited:

iceisfun

Member
Jul 19, 2014
30
4
8
Do you have any access lists assigned on the switch at all?
No access lists

I have disconnected the nexus for debugging right now but its something like this and i've tried vlan dot1q native vlan and no vlan dot1q native vlan

vlan 1-255

interface et1/1
switchport mode trunk

interface et1/64
switchport mode trunk

interface mgmt
... management ip info ...
 

Discountsocks

New Member
Aug 16, 2018
8
7
3
Seems like a basic vlan config... did you look into STP? you can set the port to be an edge device on the hyper-V link with:

spanning-tree port type edge trunk
 

azev

Active Member
Jan 18, 2013
757
233
43
I used Nexus 3000 switches at my home lab and native vlan works just fine. I think you are missing a command:

Switchport trunk native vlan XXX
 

iceisfun

Member
Jul 19, 2014
30
4
8
I had switchport trunk native vlan 1 which appears to be the default configuration for all ports,
 

maze

Active Member
Apr 27, 2013
571
95
28
Yeah, when something doesnt work in the switches network, always check your spanning tree and if you see mac addresses on the different ports/vlans :)