Hey,   It's not specific to VLAN 1. It's just having traffic tagged with management VLAN going through the trunk link between a MR and MS which causes this problem.   If your management VLAN is 99, the link would expect "tagged" traffic from all VLANs except VLAN 99. VLAN 99 frames in this case should be untagged. So if your main VLAN is VLAN 99 (i.e. same VLAN as management VLAN) and you enable tagging, it would create this problem of management VLAN traffic being tagged when it normally shouldn't have been.    Hope that helps, Aman Gupta ... View more

Hi,   Since your management VLAN is set to 1, when you tag your main VLAN as 1 on the MR, it unfortunately creates a problem. The trunk link between the MR and MS is expecting packets for all VLANs except the management VLAN.   Changing the main VLAN to anything other than VLAN 1 should fix this issue.    Hope that helps, Aman Gupta ... View more