Purpose
For instructions on how to enter Tech Support Mode for VMware ESXi 4.0 and 3.5, see Tech Support Mode for Emergency Support (1003677).
Resolution
Tech Support Mode
Tech Support Mode (TSM) provides a command-line interface that can be used by the administrator to troubleshoot and correct abnormal conditions on VMware ESXi hosts. TSM can be accessed in two ways:
- Logging in directly on the console of the ESXi server.
- Logging in remotely via SSH.
Both of these methods can be disabled, and an optional timeout value can be configured to disallow local and remote TSM access after the specified timeout period.
Note: Any existing open sessions are not automatically terminated at the end of the timeout period.
Using Tech Support Mode
Tech Support Mode is provided for the purposes of troubleshooting and remediation. VMware support may provide directions to use TSM in many forms including but not limited to telephone, E-mail, knowledge base articles, documentation, and remote desktop.
VMware recommends using the vSphere Client or any other VMware Administration Automation Product to perform routine ESXi host configuration tasks that do not involve a troubleshooting scenario. For scripting and automation, VMware recommends using the vCLI, PowerCLI, or the vSphere SDK instead of TSM.
TSM may be required to test and debug pre, post, or first boot scripts that are used in conjunction with the new ESXi 4.1 scripted installation feature. VMware recommends limiting testing and debugging these scripts to non-production environments prior to roll-out into production.
Enabling and Accessing Tech Support Mode
To enable local or remote TSM from the Direct Console User Interface (DCUI):
- At the DCUI of the ESXi host, press F2 and provide credentials when prompted. Press F2 again to proceed.
- Scroll to Troubleshooting Options and press Enter. This opens the Troubleshooting Mode Options wizard.
- To enable local TSM allowing users to log into the virtual console of the ESXi host.
In ESXi 5.x, select Enable ESXi Shell and press Enter. The right-hand panel mode should now indicate ESXi Shell is Enabled.
In ESXi 4.1, select Local Tech Support and press Enter. The right-hand panel mode should now indicate the Local TSM is Enabled. - To enable remote TSM allowing users to log in via SSH on the virtual console of the ESXi host.
In ESXi 5.x, select Enable SSH and press Enter.The right-hand panel mode should now indicate the "SSH is Enabled".
In ESXi 4.1, select Remote Tech Support (SSH) and press Enter. The right-hand panel mode should now indicate the "Remote TSM (SSH) is Enabled". - Optionally, if you want to configure the timeout for TSM:
In ESXi 5.x, select Modify ESXi Shell timeout and press Enter. Input the desired timeout value in minutes and press Enter.
In ESXi 4.1, select Modify Tech Support timeout and press Enter. Input the desired timeout value in minutes and press Enter. - Press Esc three times to return to the main DCUI screen.
To enable local or remote TSM from the vSphere Client:
- Select the host and click the Configuration tab.
- Click Security Profile > Properties.
In ESXi 5.x, select SSH or ESXi Shell and click Options.
In ESXi 4.1, select Local Tech Support or Remote Tech Support (SSH) and click Options. - Choose the desired startup policy and click Start, then click OK.
- Verify that the daemon selected in step 3 shows as running in the Services Properties window.
To enable/disable and start/stop the local ESXi Shell or local TSM from the local command line on the ESXi host:
- To start the ESXi Shell or local TSM, run the command:
ESXi 5.x – vim-cmd hostsvc/start_esx_shell
ESXi 4.1 – vim-cmd hostsvc/start_local_tsm - To disable the ESXi Shell or local TSM, run the command:
ESXi 5.x – vim-cmd hostsvc/disable_esx_shell
ESXi 4.1 – vim-cmd hostsvc/disable_local_tsm - To stop the ESXi Shell or local TSM, run the command:
ESXi 5.x – vim-cmd hostsvc/stop_esx_shell
ESXi 4.1 – vim-cmd hostsvc/stop_local_tsm
Note: These are not persistent changes. After restarting the services or rebooting the ESXi host, the changes will be lost.
To enable/disable and start/stop SSH or remote TSM from the local command line:
- To enable SSH or remote TSM, run the command:
ESXi 5.x – vim-cmd hostsvc/enable_ssh
ESXi 4.1 – vim-cmd hostsvc/enable_remote_tsm - To start SSH or remote TSM, run the command:
ESXi 5.x – vim-cmd hostsvc/start_ssh
ESXi 4.1 – vim-cmd hostsvc/start_remote_tsm - To disable SSH or remote TSM, run the command:
ESXi 5.x – vim-cmd hostsvc/disable_ssh
ESXi 4.1 – vim-cmd hostsvc/disable_remote_tsm - To stop SSH or remote TSM, run the command:
ESXi 5.x – vim-cmd hostsvc/stop_ssh
ESXi 4.1 – vim-cmd hostsvc/stop_remote_tsm
Note: These are not persistent changes. After restarting the services or rebooting the ESXi host, the changes will be lost.
To configure the TSM timeout value from the vSphere Client:based on VMware KB
- Select the host and click the Configuration tab.
- Click Software > Advanced Settings.
ESXi 5.x – Change the UserVars.ESXiShellTimeOut field to the desired value.
ESXi 4.1 – Change the UserVars.TSMTimeOut field to the desired value. - Click OK.
To access the local TSM:
- At the main DCUI screen, press ALT+F1 simultaneously. This opens a virtual console window to the host.
- Provide credentials when prompted.
Note: When typing the password, characters are not displayed on the console.
To access the remote TSM:
- Open an SSH client.
- Specify the IP address or domain name of the ESX host.
Notes: - Directions may vary depending on what SSH client you are using. For more information, consult vendor documentation and support.
- By default, SSH works on TCP port 22.
- Provide credentials when prompted.
Based on VMware KB 1017910