These switches run a single instance spanning tree by default.  This means that a spanning tree is formed based on any physical loops in the network.  So even if you do not have logical loops (because of vlan segmentation) the switch will remove ports that form a physical loop.  If I understand you description, you have 2 physical connections between the switches, one for untagged traffic and one for tagged traffic.  Spanning-tree is disabling one of these connection on one of the switches.  You can see the spanning tree port state on the STP Port Setting page.   To fix this, you can disable spanning tree globally (STP Global Settings page)or on the ports connect the 2 switches (STP Port Settings page).  Your choice will depend on you confidence of never having a loop in your network

Hi,

I have a problem. We have Dell 2824 main switch in the server, I have recently changed g1 from vlan 1 to 8 without thinking that 1 is a default for vlan. Now, I cannot login or access in the switch management and it says "This site can't be reached 192.168.1.254 Takes too long to respond"

How can I go back to default vlan? Or retrieve the setting into its default. Please, help.

Any help would be much appreciated, thank you very much.

Regards,
Dang

There are no ports for Vlan 1. How to make console connection and make changes from the CLI. 

Thank you. 

Hi,

Thank you for the help. I am hesitant to do this right away. Will it affect the internet? As some of our offices are connected to this switch. 

Regards,

Dang

Hi,

I have already applied the changes to switch. But it did not work. I though this gonna work..