Restart management agents ESXi

Restart management agents ESXi

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One error message VMware ESXi gives is saying, “Virtual machine creation may fail because the agent is unable to retrieve VM creation options from the host” as this message displays that the ESXi management agent isn’t communicating with the host during troubleshooting scenarios, and you need to perform restart management agents ESXi procedure.

When you can not connect the ESXi Server to vCenter or when you cannot connect to the ESXi Server from the client, it may be necessary to restart the management agents of the ESX or ESXi host.

Network management aims to ensure that the IT side of the business is set up in a flexible, sensible way, which can minimize disruption, provide high performance and help you avoid security issues.

Due to the fact that physical networking connects computers via cables and other hardware, virtual networking extends these capabilities by using management software to connect computers and servers over the Internet.

You isolate the VMware vSphere Client resource connections from the public network by designating a specific management network. The management network is where the VCH endpoint virtual machine links to the vCenter Server and the ESXi hosts. VCH uses this network to provide the Docker API attachment function.

Why restart ESXi management agents?

Why do you want or need to restart ESXi management agents? There are various issues I have seen in the past that have prompted the need to continue with ESXi-host management agents.

There were periods when we could note where the file would be in benefit for a particular virtual machine or some other used situation in which resources were locked.

Moreover, restarting the management agents should resolve these issues. You can restart the management agents using the Direct Console user interface:

  • Connect to the ESXi host console;
  • Press F2 to customize the host and login as root;
  • Go to Troubleshooting Options and select Restart Management Agents.

The function of ESXi management agents

ESXi management agents are used to synchronize VMware components and enable access to the ESXi host from the vCenter server. VMware agents are included in the standard configuration and are installed when installing ESXi.

Two primary ESXi agents may need to be restarted if ESXi host, vpxa and host connectivity issues occur.

  1. vpxa is the VMware agent activated on the ESXi host when the ESXi host connects to the vCenter server. There is also an example where vpxd on the vCenter server communicates with vpxa on ESXi hosts while vpxa is the VMware agent running on the ESXi site and vpxd is the demon running on the vCenter site. vpxa communicates with the host of ESXi hosts. VMware vpxa is an intermediary service for communication between vCenter and the host.
  2. hostd is used for communication between ESXi and vmkernel. hostd is the host agent responsible for managing most ESXi-host operations and registering VM, visible LUN, and VMFS volumes. hostd is accountable for starting and stopping VMs and similar vital tasks.

Will restarting management agents affect the functionality of virtual machines?

But no worries about virtual machines. It certainly won’t affect that much, but it can affect all tasks performed on the ESXi host at reboot.

It would be best to consider that no backup tasks are performed during this operation, and no snapshots are made at the moment.

Furthermore, the IP connection of the management service will be reduced when restarting the management agents of the ESXi hosts.

The case with the VMware vCenter

If the ESXi host is turned off, HA will continue to restart the included virtual machines before vCenter becomes unavailable. So if vCenter is turned off, the currently protected virtual machines will restart on other ESXi hosts.

Yet, you will not be able to cover new virtual machines until vCenter is available. You will also not be able to change any HA feature, such as Admission Control.

Fault tolerance (FT) will persist to work for configured virtual machines, but no new secondary will be created in the event of a malfunction. When fault tolerance is configured for a virtual machine, the vCenter Server does not have to be online to run FT.

Even if the vCenter Server is offline, the failure still emerges from the introduction to the final virtual machine. If you want exclusive features and you are ESXi 5.5 and above, you probably want to have a vCenter server, but it is not required.

You can edit/create/manage virtual machines using the vSphere client to connect directly to the host. You do not need to save a Windows license for vCenter. VMware already has a device loaded with vCenter.

Restart ESXi management agents

In VMware ESXi, to restart management services, there are several basic ways to do this, including using the DCUI menus or the SSH connection command line. Navigate to the Troubleshooting Mode Options and then select Restart Management Agents.

There is also a checkbox of sorts that let you Collect extra troubleshooting information.

After you confirm the restart of the management agents, you will see the messages Stopping management agents, click Done, and then Starting management agents.

 

Restart the management agents in ESXi using the Direct Console User Interface (DCUI)

  • Connect to your ESXi host console;
  • Press F2 to adjust the system;
  • Log in as root;
  • Use the up / down arrows to move Troubleshooting Options > Restart Management Agents;
  • Press Enter;
  • Press F11 to restart services.

Conclusion

Almost any IT person came across a repeating problem with ESXi 4.0, the management agents. Especially on one host that seems to flicker in and out of connectivity with the slightest reconfigurations.

Although this does happen to ESX at times, we can’t all be perfect. We sometimes need to take my ESXi host by the hand and comfort it, but this ESXi is a finicky thing. It doesn’t seem as challenging as its much older and more mature brother ESX 4.0.

If a PowerCLI script, for instance, had to start SSH service before attempting to restart management agents ESXi, it will try to be friendly and stop it before moving to the next host.