Topology: AR28-11 router----L2 switch----3 user network segments.
Symptoms: Configure three sub-interfaces for the Ethernet interface of AR28-11, and configure them with IP addresses in the same network segment as the user network segments. Users cannot ping to the IP address of Ethernet port of the router.
In the sub-interface of the router, configure vlan-type dot1q vid xx command.
Configure each sub-interface of the router as follows:
Ip address 192.168.1.1 255.255.255.0
Vlan-type dot1q vid 2
Ip address 192.168.2.1 255.255.255.0
Vlan-type dot1q vid 3
Ip address 192.168.3.1 255.255.255.0
Vlan-type dot1q vid 4
Configure the cascading interface of switches to trunk mode:
port link-type trunk
port trunk permit vlan 2 to 4
If the sub-interface of Ethernet port of mid-low end routers is not configured with VLAN ID, it supports IPX only; if VLAN ID is configured, it supports IP protocol.
When the sub-interface communicates with the peer through IP protocol, the vlan-type dot1q vid xx command is required, and the peer should permit relevant VLANs through.
When configuring the sub-interface of Ethernet port of mid-low end routers, pay attention to the relevant vlan information.