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FAQ

why does subinterface fail to forward packets

Let’s imagine that we have a simple topology like below:

arp-topology

Configure subinterfaces on both AR routers for VLAN tag termination:

[R1]interface GigabitEthernet 0/0/0.100
[R1-GigabitEthernet0/0/0.100]ip address 10.0.0.1 24
[R1-GigabitEthernet0/0/0.100]dot1q termination vid 100

[R2]int GigabitEthernet 0/0/0.100
[R2-GigabitEthernet0/0/0.100]ip address 10.0.0.2 24
[R2-GigabitEthernet0/0/0.100]dot1q termination vid 100

Try to ping IP address of neighboring router:

[R1]ping 10.0.0.2
  PING 10.0.0.2: 56  data bytes, press CTRL_C to break
    Request time out
    Request time out
    Request time out
    Request time out
    Request time out

  --- 10.0.0.2 ping statistics ---
    5 packet(s) transmitted
    0 packet(s) received
    100.00% packet loss

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Huawei’s equivalent of Cisco’s ‘logging synchronous’

If a router wants you to know something, it wants you to know right now!

Let’s look what will happen if you are entering a long command and the device wants you to be informed about a link’s failure:

[Huawei-acl-adv-3000]rule 10 permit ip vpn-instance vpn_labnario source 1.1.1.1 0.0.0.255 destination 1.1.1.2
Jan 15 2013 11:04:18-08:00 Huawei %%01PHY/1/PHY(l)[5]:    GigabitEthernet0/0/0:
change status to down
Jan 15 2013 11:04:18-08:00 Huawei %%01IFNET/4/LINK_STATE(l)[6]:The line protocol
IP on the interface GigabitEthernet0/0/0 has entered the DOWN state.
^
Error:Incomplete command found at '^' position.

When you click ‘Enter’ you will have to write the command once again. It is frustrating for all network administrators.

Unfortunately we cannot change it, like on Cisco’s devices, by ‘logging synchronous‘ command.

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