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SG200-26 not discovering Voice VLAN

This weekend I rebooted a bunch of network switches including our LAN SG200-26 switch. This I believe was my first reboot since upgrading to After this reboot our Cisco Voip phones didn't connect anymore. After looking into this it turns out the switch was no longer detecting the Voice Vlan that our phones are administratively set for.  Ever since I set up the SG200 I have left the default Voice Vlan setting of 1. However because our phones are Voice Vlan 3 the SG200 would show an operational status of 3.  After the reboot this weekend this no longer happen. The operational status on the switch shows VLAN 1 as well. In fact on every port that has a phone connected to it the PVID goes back to VLAN 1  (the default) instead of autodetecting the phone. I've checked and LLDP and CDP are on. I thought at first maybe I had made changes to my running config config without saving to my startup config but I don't think this is the cause. So far I've seen my problem appear similar to this one.

I don't see anything obvious so other than reseting to factory defaults, which I may not have done after upgrading the firmware, any other ideas?  When I upgrade the firmware is it a good idea to do a backup and restore of the config or just manually configure all over again?

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SG200-26 not discovering Voice VLAN

And I believe the firmware I upgraded from was It appears from the post below that the configuration format was changed and I'm wondering if this is causing problems?


SG200-26 not discovering Voice VLAN

Hi Sam, when using the auto voice VLAN you can still create the voice vlan (3) and specify it as the auto voice vlan. In some scenarios there is a luxury that cdp/lldp advertisements can make the switch do that automatically for you but that behavior is  luxury.

Please log in to the switch, create the vlan 3 and assign it as the auto voice vlan to see if your phones cover as expected (no port configuration should be expected)

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