1. Check the current configuration. For detailed configuration, see "Configuring the Asynchronous Interface."
2. Check the Telnet redirection connection between HostA and the Console server on the Console server.
Run the following command:
<Huawei> display tcp status
If the command output shows that the connection status is Established, the TCP connection has been established.
3. Check the AS interface status.
Run the following command:
[Huawei]display interface brief
InUti/OutUti: input utility/output utility
Interface PHY Protocol InUti OutUti inErrors outErrors
Async2/0/0 up down 0% 0.75% 525 0
Async2/0/1 up down 0% 0.75% 6525 0
Async2/0/2 up down 0% 0.75% 6525 0
Async2/0/3 up down 0% 0.75% 6525 0
…
In the command output:
− If PHY is displayed as up, but Protocol is displayed as down, the related redirection configuration might be incorrect.
− If an interface is displayed under inErrors, the AS cable (reconstructed from a normal RJ45 cable) might be faulty.
4. Check the redirection configuration of the AS.
5. Check whether the AS cable is correctly connected. Connect the network cable connector connecting the Console server to a service router. If the fault still persists, repeat Step 3 and check the command output.
6. Check the pin assignment of AS cable connectors. The end connecting to the Console server uses Async interface pins (X1 pins), and the other end connecting a service router uses Console interface pins (X2 pins). Check the pin assignment of the X1 pins, and the result shows that the pin assignment is different from that specified by the AR router.
Table 1-1 describes the pin assignment specified by the AR router.
Table 1-1 Pin assignment specified by the AR router
Table 1-2 shows the pin assignment of the AS cable specified by the AR router.
Table 1-2 Pin assignment of the AS cable
7. Make new AS cables according to the pin assignment specified by the AR router.
8. Connect the X1 end of the AS cable to the 8AS interface card (Console server), and the X2 end to a service router. The login succeeds, and the fault is rectified.