How to configure trunking between switch
In 802.1Q trunking, all VLAN packets are tagged on the trunk link, except the native VLAN. The native VLAN packets are sent untagged on the trunk link. Therefore, the native VLAN must be the same on both switches configured for trunking. This makes it easy to deduce to which VLAN a frame belongs when a frame is received with no tag. By default, VLAN 1 is the native VLAN on all switches.
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