Issue with new CB250

[johan-olofsson]

I have an older aruba switch with a sfp port and a multimode fiber connected to it.

then I use a networkcable to the CB250.

on the other end of the fiber is a CB350.

when I connect the fiber cable from aruba to CB250 I get link up, but no internet.

on the CB350 I see this message in the log: CDP-W-NATIVE_VLAN_MISMATCH: Native VLAN mismatch detected on interface gi16.

link is up, so I assume the correct SFP module is installed?

I have not touched the vlans, it's vlan1 on both switches. I can't log in to the aruba switch and see what it says there.

any idea what could be wrong here?

[balaji.bandi]

check the interface gi16 connected other side ?

make sure native should match both the side as expected.

cisco side default native VLAN if nothing configured VLAN1

check on the ARUBA side on the trunk port ?

https://www.arubanetworks.com/techdocs/AOS-CX/10.07/HTML/5200-7865/Content/Chp_vlans/vlan_cmds/vla-tru-nat.htm

[johan-olofsson]

I have only 1 vlan, default vlan1, not planning to add another. how do I set native vlan1 on both switchen? through the webgui then.

if that is the issue, it's only error I see on the CB350. gi16. but link is up.

[balaji.bandi]

Follow below guide :https://www.youtube.com/watch?v=wIqBfc5k8kY

Also is there any other devices or switches connected to these switches behind each switch ?

[KJK99]

@johan-olofsson 

CDP-W-NATIVE_VLAN_MISMATCH means what it says. If the gi16 on CBS350 is in VLAN1, the port on the other side of the link must be in a different VLAN. You can learn what VLAN it is by looking up the details of CDP Neighbor Information on your CBS350. CDP-W-NATIVE_VLAN_MISMATCH doesn't necessary mean a trouble, especially if you want to use your CBS350 like a dummy switch, just having VLAN1. In that case, frames leaving your CBS350 will be untagged and the switch will expect arriving frames to be untagged as well. This will probably not help, but you may try to put the gi16 on CBS350 in the VLAN shown by CDP. It needs to be a new VLAN because the default VLAN cannot be modified. If that does not help, you need to learn how the other side is configured. The answer to your Internet access trouble is most likely there or in your Internet router. As long the smartport feature and IPv4 routing is disabled on your CBS350, I don't think there's anything wrong with it. You may also like to disable CDP since you probably do not need it. There is also a CLI command that shows the fiber-optic module info, but I can't recall the details right now. 

[Deepak Kumar]

Hello, 

My recommendation is to check the port configuration first. if VLANs are matching as you mentioned then it is a known bug in Aruba Switches. I had run this issue as well. 

Have a look at below discussions:

LLDP - Incorrect VLAN sent out ArubaOS 6.3 | Wireless Access (arubanetworks.com)

[KJK99]

Has that bug caused any problem beside polluting the log?

[balaji.bandi]

Operational this should not cause issue, this is only a Log messages, if you like you can use log discriminator to supress the logs. on cisco device side. (if the CBS small business switches support that features)

[johan-olofsson]

Beginning to think it's the SFP module..
The module is a MO-C-S85123-3CLM
According to Cisco it should be a MO-L-S85123-CLM.
Anyone know the difference between the 2? I get a green blinking light when I put in the module.. so link is established.

[balaji.bandi]

Is this Cisco SFP - if not, then worth check the compatibility.

https://www.cisco.com/c/en/us/support/docs/smb/switches/Cisco-Business-Switching/kmgmt-1524-SFP-Modules-CBS.html

i do not believe vlan native mismatch with SFP issue.

[KJK99]

Removed. Duplicate.