What is login and password to enter telnet on cisco d9850&

This needs to be discussed in different situations, you can check whether these situations can solve your current problem.
Scenario 1: All Default Passwords Are Changed and All Passwords Are Forgotten If you change all default passwords and forget the console port login password, all STelnet/Telnet login accounts and passwords, and BootROM/BootLoad passwords:
·For a switch that has the PNP button, you can press and hold the PNP button for more than 6 seconds to restore the switch to factory settings and restart the switch. The following figure shows the PNP button.
·If the switch does not have the PNP button, return it to the factory for repair.
Scenario 2: Default Passwords Are Forgotten For S series switches running V200R020 and later versions, no passwords are configured for default accounts, and users must configure new passwords for logging in to the switches. In this situation, scenario 2 is not involved.
However, for S series switches running versions earlier than V200R020, there is no default STelnet/Telnet login password, but there are default console port login password, default BootROM/BootLoad password, and default web login password. These default passwords may vary according to the switch version.
If you always use the default passwords and have not changed the passwords, you can obtain the default accounts and passwords according to S Series Switches Default Usernames and Passwords (for enterprise users or carrier users). The permission level of this document is C (customer support level). If you need to upgrade the permission level, see the help document on the website.
Scenario 3: The Console Port Login Password Is Forgotten Three methods are available to recover the console port login password.
·Method 1: Log in to the device using STelnet or Telnet and change the console port login password.
·Method 2: Clear the console port login password in the BootROM/BootLoad menu and change the console port login password.
Scenario 4: The STelnet/Telnet Login Password Is Forgotten ·If you forget the login password of an STelnet/Telnet account, you can use another STelnet/Telnet account with administrator rights to log in to the device and reset the password. For details, see Method 1.
·If you forget the passwords of all STelnet/Telnet accounts but can log in to the device through the console port, see Method 2.

Method 1: Use an STelnet/Telnet Account with Administrator Rights to Log In to the Device and Reset the Password

1.Log in to the switch using the STelnet/Telnet account with administrator rights.
2.Change the STelnet/Telnet login password. The following example describes how to change the STelnet/Telnet login password of VTY0 to VTY4.

Method 2: Log In to the Device Through the Console Port and Set a New STelnet/Telnet Login Password

If you forget the STelnet/Telnet login password but remember the console port login password, log in to the switch through the console port and set a new STelnet/Telnet login password.
Scenario 5: The BootROM/BootLoad Password Is Forgotten but the Console Port/STelnet/Telnet Login Is Available If you can log in to the switch through the console port, STelnet, or Telnet, log in to the switch and restore the default BootROM/BootLoad password. You can obtain the default accounts and passwords according to S Series Switches Default Usernames and Passwords (for enterprise users or carrier users). The permission level of this document is C (customer support level). If you need to upgrade the permission level, see the help document on the website.
Scenario 6: The Web Login Password Is Forgotten but the Console Port/STelnet/Telnet Login Is Available If you can log in to the switch through the console port, STelnet, or Telnet, log in to the switch and reset the web login password. In the following example, the web login user name is admin123 and the password is test@123.
For more reference resources, please click to enter (ebook) CloudCampus 3.0 Solution:
https://support.huawei.com/enterprise/en/doc/EDOC1100201111
OR you can straight to see this decument
https://support.huawei.com/enterprise/en/doc/EDOC1100200698#section1612361212554

In the below example i'm setting password as cisco for enable mode & Virtual terminals of router
1)Connect to the router and follow the below steps
Router>
Router>enable
Router#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#enable secret cisco
Router(config)#line vty 0 4
Router(config-line)#password cisco
Router(config-line)#login
Router(config-line)#exit
Router#exit
Router con0 is now available
Press RETURN to get started.


Test:
Router>enable
Password: (type cisco to enter into the router privilaged mode)
Router#

Hi

Instructions
telnet to the IP address of the Cisco switch
Enter the telnet access password for the Cisco swict when requested, and then the "Enter" key.
Type "enable" at the command prompt, and then the "Enter" key.
Enter the Privileged Exec password when requested at the command prompt, and then the "Enter" key. Then enter "configuration terminal" at the command prompt, and then the "Enter" key.
Type "interface fastethernet0/1," replacing the "fastethernet0/1" with the name of an interface in which you wish to enable PoE, and then the "Enter" key. Then, while in interface configuration mode, type "power inline auto" and then the "Enter" key. Repeat this step for each interface in which PoE is required.
Type "end" at the command prompt and then the "Enter" key, copy running-config
Below is some commands to run, I don't have any power on the interface but this will show you if this is working...
SW1#sh power inline fastEthernet 0/1
Available:360(w) Used:0(w) Remaining:360(w)
Interface Admin Oper Power Device Class Max
(Watts)
--------- ------ ---------- ------- ------------------- ----- ----
Fa0/1 auto off 0.0 n/a n/a 15.4
Run this command to see the interface is up.....
SW1# sh interface fastEthernet 0/1 ' in protocol
FastEthernet0/1 is up, line protocol is up (connected)
SW1#sh cdp interface fastEthernet 0/1
FastEthernet0/1 is up, line protocol is up
Encapsulation ARPA
Sending CDP packets every 60 seconds
Holdtime is 180 seconds


Thanks

yes, you should be able to connect to the console port using a roll-over cable RJ45-DB9, connect using hyper terminal or similar using the com port settings 9600,8,N,1
You can then configure the switch from the CLI...

Have you set the 'Login' command on the VTY lines in the switch setup and an IP address on the management VLAN to connect to.
You also HAVE to have a password enabled on the vty lines in order to connect via telnet.

hope this helps.

login through telnet, remove the current username and password.

configure the username with the new password

config t
username xxxx pass xxxx

1. do not exit the current session, telnet the sw with new session and give the username and new pass. if does'nt work roll back the config.

or

2 excute login in current session and try with the username and new pass

From a console login, should look something like this:

Switch>

Go to privileged EXEC mode with the command "Enable"

Switch#
Enter the command "erase startup-config"

It will prompt you to confirm
When you confirm, it will bring you back to this prompt

Switch#

Now, enter the command "reload"
It will prompt you to confirm. And after a reload, you will be brought back to a screen that looks like this:

Press ENTER to begin

NOTE: if you are telnetting to the switch it WILL boot you out as you cannot keep an established telnet session without VTY line passwords and those are cleared by this process.

ALSO NOTE: This will NOT erase your VLAN data, VLANs are stored in a special file in Flash on a Cisco switch and SHOULD NOT be erased without professional help as there is a risk of destroying the IOS load on the switch.

Did you setup telnet login and password? Are plugged into a port that is disabled or not programmed right.

Use this step:Router>enable Router#config t Router(config)#line vty 0 4 Router-2(config-line)#login% Login disabled on line 66, until 'password' is set % Login disabled on line 67, until 'password' is set % Login disabled on line 68, until 'password' is set % Login disabled on line 69, until 'password' is set % Login disabled on line 70, until 'password' is set Router-2(config-line)#password newpasword

Does this mean anything to you Remote Login Names and Passwords During a remote login, the device prompts you for a login name and password. You can display the login name when logged in to the device from a remote console by using a device status command. Logging in Remotely or Locally Logging in to a local console is the same as logging in to a remote console except that you must connect to the device by starting Telnet on your host system. To log in remotely, begin at step 1. To log in locally, begin at step 3. To log in from a remote console: 1. Connect to the device by starting Telnet on your host system. Your host system is the system to which remote terminals are connected. 2. Supply the device?s name or Internet Protocol (IP) address. To use device names, your network must have a name server. Issue either the device name or the IP address as shown in the following example: % telnet brandenburg or % telnet 128.185.132.43 At this point, it makes no difference whether you have logged in remotely or locally. 3. If you are prompted, enter your login name and password. login: Password: It is possible that there is a login and no password. The password controls access to the device. If a password has not been set, press the Enter key at the Password: prompt. Logins are not set automatically. For security, you can set up user names and passwords using the add user command in the CONFIG process. For additional information, see the add user configuration command, on 56. Remember to reload or restart to activate any changes. Note: If you do not enter a login name and valid password within 1 minute of the initial prompt, or if you enter an incorrect password three times in succession, the device drops the Telnet connection. 4. Press the Enter key to display the asterisk (*) prompt. You may have to press the Enter key more than once or press Ctrl-P to obtain the * prompt. Once at this level, you can begin to enter commands from the keyboard. Press the Backspace key to delete the last character typed in on the command line. Press the Delete key or Ctrl-U to delete the whole command line entry so that you can reenter a command. See ?Command Completion? on page 20 and ?Command History? on page 23 for more information. You can also use local Telnet commands on your Telnet client to close the Telnet connection.