Fiber optic ports are not working after VLANs are created on the main switch

Check for link status on switch ports; ensure they are up and not in a disabled or error state. Confirm that the VLAN configurations on both ends of the link match. There are no specific requirements ...

Factory
Dec 15, 2025

Fortswitch not working over fiber : r/fortinet

Also use a proper cleaning tool when cleaning fiber ends and optics. If the fiber is terminated at a panel, you could also try swapping

Factory
Sep 06, 2025

Fiber port of switch does NOT working

This is a quick video with a few tips I''ve picked up over the years for working with fiber connections on Cisco

Factory
Sep 21, 2025

Re: Fiber Ports Not Getting Config Correctly

My guess: You used these ports previously on the older firmware, which required a license in order to use 10G.

Factory
May 17, 2026

Managed switch in 2nd building connected to main switch stack by fiber

The port the WAP is connected to is tagged in VLAN ID 5 and 6. I plugged in another WAP into a managed switch connected by fiber

Factory
Dec 23, 2025

New Added Vlan on Port Channel is not showing on VPC active vlan link

Dear Community, I have two nexus switches Switch A and Switch B running as VPC. I am working by Switch profile. I

Factory
Apr 03, 2026

Troubleshooting VLAN Connectivity Issues

There can be a few different causes for VLAN connectivity issues: Incorrect configurations of the virtual portgroups

Factory
Dec 05, 2025

How to Troubleshoot Common VLAN Interface Issues | NSC

Disable Unused Ports: Disable all switch ports that are not in use, effectively reducing the number of entry points an

Factory
Jun 10, 2026

Fiber port of switch does NOT working

2960X switch = 1/4 port is currently plugged with Cisco GBIC module. - I plugged new Fiber cable with new GBIC

Factory
Jan 26, 2026

Multiple VLANs over Fiber : r/HomeNetworking

Multiple VLANs over Fiber I''m moving into a new house and one of the first orders of business will be setting up my network. I''m not

Factory
Jun 06, 2026

VLAN separation across Fiber Ports

I have a 3850-24xs Fiber switch and four c2960x 3 switch stacks with 3 fiber runs back to the Fiber switch. te1/1/1 and

Factory
Nov 08, 2025

How do you troubleshoot VLAN connectivity issues?

Check for link status on switch ports; ensure they are up and not in a disabled or error state. Confirm that the VLAN

Factory
Feb 26, 2026

Fix VLAN Misconfiguration: Step-by-Step Guide

Incorrect VLAN settings can cause traffic disruptions, unauthorized access, and inefficient network performance. This guide will help

Factory
Apr 22, 2026

Half of my main network switch has stopped working

Half of my main network switch has stopped working. Irritatingly I can''t get to the Web interface through the remaining ports due to

Factory
Jan 06, 2026

How to perform VLAN troubleshooting

How to perform VLAN troubleshooting Common VLAN issues include physical connectivity problems, duplex

Factory
Oct 05, 2025

Solved: VLAN doesn''t add port

I got it working! Even after disabling BDPU and spanning-tree on port te2/4, it wouldn''t ping. I got in touch with another

Factory
Mar 13, 2026

VLANs under fortiswitch

I''ve created my VLANs under WiFi & Switch Controller > Fortiswitch VLANs with their IP range and Mask . I''ve

Factory
Feb 20, 2026

Troubleshoot Fiber Links on Catalyst 9000 Series Switches

This document describes how to troubleshoot fiber optic interfaces by addressing some of the fiber optic module and

Factory
Mar 05, 2026

Configure Port to VLAN Interface Settings on a Switch through

This article provides instructions on how to configure an interface VLAN as an access or trunk port on your switch

Factory
Apr 12, 2026

Fix VLAN Misconfiguration: Step-by-Step Guide

Introduction VLAN (Virtual Local Area Network) misconfiguration can lead to network segmentation issues,

Factory
Feb 24, 2026

Virtual Network (VLAN) Troubleshooting

Virtual Network (VLAN) Troubleshooting UniFi makes it easy to create and manage virtual networks (VLANs), however certain

Factory
Dec 02, 2025

Troubleshooting VLAN and Switch Problems

Learn how to troubleshoot VLAN and switch problems in the first of this two-part series by Joe Rinehart. Video Tutorial.

Factory
Nov 13, 2025

Vlans trunking fiber optic connection

Hello All, At a customer of us we have te following problem. I tried some things but it still doesn''t work. There a 2

Factory
Mar 12, 2026

Solved: What would cause all fiber optic ports on a switch to go down

It seems that the whole fiber optic controller stops working for some external cause, like there''s something that

Factory
Feb 06, 2026

3850 VLANs and Switchports not coming up

I am trying to replace a 3750 Switch with a 3850 Switch. When I attempt to insert the 3850 into production, none of the

Factory
Sep 12, 2025

Solved: vLANs, Fiber

We have two buildings 2103 and 2080 these are currently connected by a 20Mb/s MAN. We just ran fiber and we

Factory
May 28, 2026

VLANs over fiber and FastIrons. Can someone help me out?

Hey everyone, OK, back to wireless again (after the project got pushed back a few days). This is all for wireless

Factory
Sep 09, 2025

Cisco VLAN Troubleshooting Commands And VLAN Issues

This article offers practical tips and solutions for VLAN troubleshooting, including how to verify VLAN tagging, and

Factory
Oct 01, 2025

Configuring VLANs on Cisco Switches

Master configuring VLANs on Cisco switches. Learn to configure Access and Trunk ports, and Native VLANs and Allowed VLAN

Factory
May 26, 2026

Common Problems with Inter-VLAN Routing and How to Fix Them

Troubleshoot common inter-VLAN routing problems with this guide. Learn to diagnose and fix issues like VLAN

Factory
Jul 10, 2026

Troubleshooting VLANs

CoPP for TFTP traffic only matches the TFTP connections on the ports and it does not match the concurrent data transfers that are

Factory
May 18, 2026

Solved: Vlan NOT passing through trunk port

This should be a very basic fix, but I can''t seem to find the answer. I have a Cisco C2960-L switch & Cisco 1921 router.

Factory
Apr 17, 2026

VLAN Configurations: Setting and Troubleshooting | NSC

A trunk port on a switch can carry traffic for multiple VLANs, but the traffic from the native VLAN is not tagged with a

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