Step 1: Check whether the number of login users reaches the upper limit.
Log in to the device through the console port and run the display users command to check whether all VTY user interfaces are in use. By default, the maximum number of VTY user interfaces is 5. You can run the display user-interface maximum-vty command to check the maximum number of login users allowed by the device.
If the number of login users reaches the upper limit, run the user-interface maximum-vty command to increase the maximum number of login users to .
Step 2: Check whether an ACL is configured in the VTY user interface view (Telnet IPv4 is used as an example).
Run the user-interface vty command on the Telnet server to enter the user interface view and then run the display this command to check whether an ACL is configured in the VTY user interface view. If so, record the ACL number.
Run the display acl acl-number command on the Telnet server to check whether the IP address of the Telnet client is denied in the ACL. If so, run the undo rule rule-id command in the ACL view to delete the deny rule and then run the corresponding command to modify the ACL and permit the IP address of the client.
Step 3: Check whether the access protocol is correctly configured in the VTY user interface view.
Run the user-interface vty command on the Telnet server to enter the user interface view and then run the display this command to check whether protocol inbound is set to telnet or all. By default, the system supports the protocol. If not, run the protocol inbound { telnet | all } command to allow Telnet users to connect to the device.
Step 4: Check whether an authentication mode is set for login users in the user interface view.
If password authentication is configured using the authentication-mode password command, you must enter the password upon login.
If AAA authentication is configured using the authentication-mode aaa command, you must run the local-user command to create a local AAA user.
For details, see the S Series Switches FAQ.
Step 1: Log in to the enterprise technical support website at http://support.huawei.com/enterprise.
Step 2: Click Switches.
Step 3: Click the name of the product to be queried, for example, S7700.
Step 4: Choose Documentation> S7700&S9700 Series Switches FAQ to find the FAQ for your switch model.
Step 5: Open the FAQ. Choose Basic Configuration> Why Does Telnet Login to a Switch Fail in the navigation tree on the left, and follow the instructions.
S7700&S9700 Series Switches FAQ
http://support.huawei.com/enterprise/en/doc/EDOC0100547869?idPath=7919710|21782164|21782186|22318632|6805481
This post was last edited by All_About_Switch at 2018-05-10 07:24.
