VM failed and won't start. Displaying "An emulator required to run this VM failed to start"
-
/dev/sdb: open failedThat's your issue. Can you check if your SR is correctly connected? Are you using Qcow alpha?
-
@olivierlambert said in VM failed and won't start. Displaying "An emulator required to run this VM failed to start":
Qcow alpha
No Qcow alpha. I do have three other host with no issues that I know of (Hopfully) attached is the Storage Screenshot on that host.
-
Check the SR view in XO, hosts tab to see if they are all connected.
-
-
Do a
lsblkon the problematic host, let's see what's /dev/sdb -
-
So first, how does "AlmaLinux8-Testing" appear in XO? Like started? If it's the case, you might do a state power reset to it. Then, check the
dmesgon the host, I have a feeling there's a connection issue with it. -
@olivierlambert "Failed","Shutting down VM 'AlmaLinux8-Testing' on 'iahost-xcpng-server3'
Internal error: Object with type VM and id dfcdcce6-b6e1-d865-6f2b-472a35b1fae7/config does not exist in xenopsd","iahost-xcpng-server3","Jun 9, 2025 12:28 PM" -
That's why you need to power reset it first.
Also please check the host
dmesg -
@olivierlambert Oh, I'm sorry. You mean power restart the host server?
-
[12:52 iahost-xcpng-server3 ~]# xe vm-reset-powerstate vm=dfcdcce6-b6e1-d865-6f2b-472a35b1fae7 --force
This operation cannot be completed because the server is still live.
host: 6985c3a2-091d-488b-8de6-4bf40985987b (iahost-xcpng-server3) -
On the pool master:
- Restart the toolstack
- Immediately after, run the vm reset powerstate command.
-
@olivierlambert Ok. I was able to get that VM started on another Host. Now, I need to figure out what is going on with server1. I appreciate all your help! If you have any suggestions please let me know.
-
My suggestion stands from previous messages, check the
dmesgoutput from the problematic host
-
@olivierlambert It is full of these:
43342477.643853] sd 7:0:0:1: rejecting I/O to offline device
[43342477.643861] print_req_error: I/O error, dev sdb, sector 0 -
That's exactly what I suspected. You have a connectivity issue with your shared storage.
The device is considered offline because it cannot do any I/O on sector 0
-
said in VM failed and won't start. Displaying "An emulator required to run this VM failed to start":
rejecting I/O to offline device
I was able to reboot the host. Now things seam fine. Does that make sense? I mean have you seen this happen then a reboot of the host takes care of it?
-
@olivierlambert I had the same issue this morning on one of the hosts I rebooted and was working fine. An emulator required to run this VM Failed to start. sd 7:0:0:1: rejecting I/O to offline device. I am not sure what to check next.
-
xcp-ng iscsiadm -m session -P 3 Attached scsi disk sdb State: offline
-
There's something fishy about the connectivity to your storage.
Hello! It looks like you're interested in this conversation, but you don't have an account yet.
Getting fed up of having to scroll through the same posts each visit? When you register for an account, you'll always come back to exactly where you were before, and choose to be notified of new replies (either via email, or push notification). You'll also be able to save bookmarks and upvote posts to show your appreciation to other community members.
With your input, this post could be even better 💗
Register Login