How to move your VMs from a dead ESXi host

//How to move your VMs from a dead ESXi host

How to move your VMs from a dead ESXi host

This weekend we lost an ESXi 6.0 host from a Cluster of 8 hosts(with shared Storage between them). This is a particularly ESXi host/Cluster since HA is not enabled and vMotion between hosts is not possible since the VMs needs to run in a particular host and local network. There is also some VMs that have share disks.

There was no backup of the ESXi host configurations, so this means that we need to do all from scratch and precisely like the fault ESXi host so that VMs could start and use some networks(vSwitch or vDS).

So after a dead SDD Card(where the ESXi host is installed), all VMs were not accessible through vCenter(but you could browse the VMs and their folders). So we could browse and choose one of the VMs and then add to inventory. But when you have hundreds of VMs and many Datastores is a pain to find the VMs and also the Datastore where was allocated in the beginning.

We can check this information in same places, and SQL DB(searching VM information) is one of those, but the fastest way is to search manually in the /vmfs/volumes folder with the command find. -name VMName.vmx, then you need to register the VM manually again.

How To

First, we need to add a new host to Cluster, or we can use an existing one. But like I said this is a special ESXi that needs VMs allocated to particularly hosts to run unique VMs, so moving VMs to other hosts is not possible. So I need to install from scratch a new ESXi for this case(but in your case the same tasks can be done in the host that already exists).

One of the problems, when you need to install an ESXi host from scratch to replace a dead one that had a lot of Local Networks(vSwitch), is to identify which the ESXi had.
The easy and fastest way is before we remove the dead host from the vCenter is to click in the ESXi and wait a couple of minutes so that vCenter check the host is down, but will display the old information and then you can see the local network in the network board.

How to move your VMs from a dead ESXi host

After we check witch Standard Switch(vSwitch) were in the previous ESXi host, we can then create in the new host.

Note: Another alternative is to go to Home -> Inventory -> Network and then check all vSwtich one by one and at the same time in each one click in the Hosts tab and we can double check if this network was from the fault ESXi. But if you have too many vSwitch, this will take more work. So if the above solution shows you the information that you need, use it.

After we have our new host with all the needed networks(also don’t forget to add the host to any vDS that the fault host was in), we can start the work to recover all VMs and register them in the new host.

Log in to the new ESXi host shell console and do next tasks.

Using the command find .name and the VM name we will find the VM location and then we can use the command vim-cmd solo/registervm to register the VM in the ESXi host that we are in.

Option 1: Use Find command to find where you VMs are located

To check the VMs name list, you can do the same you did to check the Networks, but click in the dead host and then in the tab “Virtual Machines”. See the next image.

How to move your VMs from a dead ESXi host

Just go to the /vmfs/volumes folder(so that will be faster your search), but you can search from the root also.

[root@localhost:/vmfs/volumes] find . -name VMName.vmx./9a21a847-635042f7/VMName/VMName.vmx

You will get the full path of the VM in the Datastore. If you are using this step, jump option 2 and go to the register VM step.

Option 2: Find all VMs bound to a specific host.

In this case, you can use the vCenter DB and run the following SQL query. This will list you all VMs that was registered in the dead ESXi host.

“SELECT vpxv_vms.NAME, vpxv_vms.hostid, vpxv_hosts.NAME, VPXV_VMS.CONFIGFILENAME, vpxv_hosts.DNS_NAME FROM vpxv_vms
JOIN vpxv_hosts on VPXV_VMS.HOSTID = VPXV_HOSTS.HOSTID
WHERE vpxv_hosts.DNS_NAME = ‘host DNS NAME’
and ((vpxv_hosts.hostid = vpxv_vms.hostid))”

Note: If you are not sure of your ESXi host DNS Name do a nslookup with the IP Address to get the ESXi Host Full DNS Name.

We will also get the column name VMS.CONFIGFILENAME that shows in witch Datastore the VM is allocated.

After you have your VMs full list or just one by one, you can do the above commands to register the VM in the new ESXi host.

[root@localhost:/vmfs/volumes] vim-cmd solo/registervm /vmfs/volumes/9a21a847-635042f7/VMName/VMName.vmx

Note: If you have a VM Template don’t forget that the configuration file is not .vmx, but .vmtx. So your search and register need to use the proper VM configuration file extension.

Do the above tasks for all VMs that you have in the list above. After all, VMs will ready to power on in the new host.

But since we have change host, and force a VM move, sometimes we can see some issues in the VMs when we power up.

First: Since we move a VM without a vCenter, the vCenter did not have a registry of that move, you can have the following question:

How to move your VMs from a dead ESXi host

Since this was a move, we will choose the “I Moved It” option. With this no changes in the settings and VM UUID. You can read more about this HERE.

Second: The VM Virtual Network interface may not be enabled, and if we try to enabled, we get an error(something similar to Invalid configuration for device ‘0’).
You can check this issue HERE. In the VM log(vmware.log) we will see something like “Virtual device Ethernet0 will start disconnected”.

This only happens to Virtual Interfaces connected to vDS. But the easy way to fix the issue is to change the Network to another vDS or Local Network, enable the Interface and power up. After you power on the VM, you can now shift back to the original vDS Portgoup.

After all these changes and tasks all VMs are working correctly and registered in the new host.

Hope this can help bypass this error in the future.

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By | 2019-04-14T22:12:44+02:00 August 31st, 2016|Virtualization|0 Comments

About the Author:

I am over 20 years’ experience in the IT industry. Working with Virtualization for more than 10 years (mainly VMware). I am an MCP, VCP6.5-DCV, VMware vSAN Specialist, Veeam Vanguard 2018/2019, vExpert vSAN 2018/2019 and vExpert for the last 4 years. Specialties are Virtualization, Storage, and Virtual Backups. I am working for Elits a Swedish consulting company and allocated to a Swedish multinational networking and telecommunications company as a Teach Lead and acting as a Senior ICT Infrastructure Engineer. I am a blogger and owner of the blog ProVirtualzone.com

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