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it_medcompFlag for United States Minor Outlying Islands

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Need help with VLAN issue

We have a couple of VLANs configured, and a recent outage. At this point, we are down to figuring out why it is still down. I have two switches in two different buildings. Everything works on switch 1. Switch 2, general network equipment works- except the VOIP phones. The obvious issue is something is plugged in to the wrong place.
We have 2 VLAN's, VLAN1 and VLAN200. 1 works fine. the VLAN setup is as follows:
Tagged ports: 1-44, 48
Untagged: 46
Forbidden: 45, 47
The uplink connects to port 1. There is no link on port 46, which is labeled VLAN200. I Know that connecting the right cable to port 46 will fix the problem.
. The uplink on port 1 connects to port 1 on switch 1, where all of the devices attached work. Both switches are identical- same model, same port designations, etc. That port is tagged on both switches- shouldn't both VLANs pass traffic to the right VLAN over that port?
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Dan Craciun
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1. So port 1 is trunk on both switches. What VLANs does it allow?
2. Are the VOIP phones on VLAN 200? If so, where are the packets tagged?

>>That port is tagged on both switches- shouldn't both VLANs pass traffic to the right VLAN over that port?
Not necessarily. If the packets in switch 2 are never tagged as VLAN200, then they will be passed as VLAN1 in switch 1.

HTH,
Dan
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Port 1 appears to be a trunk, perhaps in the virtual sense since it is a member of both VLANs- but it is not defined by the switch as an official "Trunk". It is an untagged port on VLAN 1 and a tagged port on VLAN200. Phones sit on VLAN 200 and VLAN200 does not have connectivity. Port 46 is the one labeled as VLAN200 and the same port on the other switch shows link on the other switch...

The phones are tagged on ports1-44 and 48- 45 and 47 are forbidden and reserved for other uses, and 46 is untagged on VLAN200. I don't think the problem is configuration- I am pretty sure it is a cabling problem. What happened was there was an outage, cause unknown, and part of the troubleshooting involved unplugging all the cables- the most likely point of failure is cables being plugged in. Do you think that moving the uplink cable coming from port 1 on switch 1 from switch 2's port 1 to switch 2's port 46 might resolve the issue?I've worked some with VLAN's but never quite like this....
>>46 is untagged on VLAN200
That is a contradiction. If you want packages to be part of a VLAN, they need to have a tag that says "hey, I'm from 200".

I assume that port 46 is an access port.

If there are 2 ports marked as VLAN200 in the 2 switches, I would try connecting them to each other first.
Thanks for the explanation. I don't converse in VLAN speak much.... so to word it better, port 46 is an untagged member of VLAN200. I have 1 cable that comes in from the switch 1- which is located in another building. Unfortunately, I have little to go on besides the port labels, which were set up a few months ago. The only ones in question though are on Switch 2 since all devices are working properly on switch 1. Most of the general ports are labeled PC/PHONE so I know the VLAN ingresses/egresses only would have been used as such by the two ports... and I have 1 wire... and I have to choose between uplink and VLAN200. I guess the next step is to move the cable in Uplink to VLAN200. I'll take any advice!
THanks.
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Dan Craciun
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Thanks everyone for your help. we resolved the issue last night- Looking at the VLANs was actually a step more complex than we needed to make it- We resolved it using LLDP neighbor queries with a small amount of guesswork. It was definitely a cabling issue, though initially it looked like we might have lost a configuration- due to an incorrect management setting!
Thanks so much for the help!