[Redirected] Troubleshooting virtual machine console and MKS issues in the vSphere Client
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Article ID: 321529
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Updated On:
Products
VMware vCenter ServerVMware vSphere ESXi
Issue/Introduction
When you try to connect to a virtual machine console from vCenter Server, you see these errors:
Error connecting: Host address lookup for server <SERVER> failed: The requested name is valid and was found in the database, but it does not have the correct associated data being resolved for Do you want to try again?
Error connecting: cannot connect to host <host>: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond. Do you want to try again?
Error connecting: You need execute access in order to connect with the VMware console. Access denied for config file.
Unable to connect to MKS: failed to connect to server IP:903.
Note: Looking at the virtual machine logs (vmware.log), errors with the console will appear as MKS (Mouse,Keyboard,Screen).
You cannot open a remote console to a virtual machine.
Virtual machine console is black (blank).
The VMware vSphere Client console tab session may time out or disconnect while in use.
Migration of virtual machines using vMotion fails.
This issue may affect a single ESXi/ESX host. If the virtual machines are moved to another ESXi/ESX host, you may be able to connect to the console without issues.
This issue may occur if you try to connect to the console using the VMware vSphere Client connected directly to the ESXi/ESX host or to vCenter Server.
This issue may occur if your network contains a firewall between the ESXi/ESX host and the vSphere Client.
Validate that each troubleshooting step below is true for your environment. The steps will provide instructions or a link to a document, for validating the step and taking corrective action as necessary. The steps are ordered in the most appropriate sequence to isolate the issue and identify the proper resolution. Do not skip a step.
Log in to vCenter Server directly through Terminal Services or a Remote KVM and attempt a connection using the vSphere Client from this system. If this method works, a firewall may be preventing the console from connecting.
Note: If port 903 is not open or cannot be opened in your environment, enable the vmauthd proxy. This forces remote console communication to be sent on port 902 on the Service Console, instead of 903. By enabling this setting there may be degradation in the performance under heavy usage while communicating to the ESXi/ESX host service console.
Note: In ESXi 4.x, 5.x and 6.0, vmauthd.server.alwaysProxy is, by default, set to true.
Verify that the ESXi/ESX host and the workstation running the vSphere Client are correctly synced to an NTP service. This is required to satisfy SSL handshaking between the vSphere Client or and the ESXi/ESX host. For more information, see Verifying time synchronization across an ESXi/ESX host environment (1003736).
DNS problems are a common cause of virtual machine console problems. Verify name resolution in your environment. For more information, see:
File a support request with VMware Support and note this Knowledge Base article ID (749640) in the problem description. For more information, see How to Submit a Support Request.
Additional Information
For more information on similar error to this article, see: