FWIW -- I had a similar problem with VMs going randomly down -- it wasn't windows but various BSD and Linux VM's. Sometimes they would run a few days, other times they would lock up every other day. Logs didn't help because when the VM locked, logs were not written. I even had the xcp-ng installation lock a few times, although it was usually on of the VMs. I started searching for faulty hardware and eventually SMART tested all the drives and mem86 the RAM. Turns out I had some bad RAM modules which I later RMA'd. With new RAM (after after thoroughly testing it), I haven't had any lock ups. I'm not sure this will help you at all.

@nikade Hey thanks for for the link. I ended up just using a LetsEncrypt cert rather than self signed. I think had to add a DNS host override on my router to associate the Local LAN address of the xo server with the domain name of the server contained in the certificate -- Like 10.0.1.50 ---> xo.example.com. Thanks for pointing me in the right direction on this one.

Small nitpick -- you can tell me to go away. Anyway to install certs so I can view the data using https?

I guess I'll label this one solved. Turns out I needed to eject the virtual iso within the virtual CD-ROM drive. Perhaps VM boot order tries to boot from DVD First (although hard drive is listed first in the boot order of XO followed by DVD followed by Network.

Not sure but I'll label this one as solved.

I had Arch VM with ZFS on root running within xcp-VM. Recently upgraded kernel and now VM will not boot. (Not sure if this is kernel related however since a few other packages were upgraded as well).

When trying to start the VM, I get the following errors from the xcp-ng (I actually pulled these from Xen orchestra logs):

vm.start
{
  "id": "98a8dc5a-66f4-a475-ec2a-3de2df439629"
}
{
  "code": "VDI_MISSING",
  "params": [
    "OpaqueRef:3d2fb686-ebd9-4e68-b93b-c036bd2f1c99",
    "OpaqueRef:07784b90-20b0-4960-8e0b-4c4dc575db55"
  ],
  "call": {
    "method": "VM.start",
    "params": [
      "OpaqueRef:d091d6c6-168a-4f6a-b365-c54cac642031",
      false,
      false
    ]
  },
  "message": "VDI_MISSING(OpaqueRef:3d2fb686-ebd9-4e68-b93b-c036bd2f1c99, OpaqueRef:07784b90-20b0-4960-8e0b-4c4dc575db55)",
  "name": "XapiError",
  "stack": "XapiError: VDI_MISSING(OpaqueRef:3d2fb686-ebd9-4e68-b93b-c036bd2f1c99, OpaqueRef:07784b90-20b0-4960-8e0b-4c4dc575db55)
    at Function.wrap (/opt/xen-orchestra/packages/xen-api/src/_XapiError.js:16:11)
    at _httpRequestPlus.default.post.readAll.then.text (/opt/xen-orchestra/packages/xen-api/src/transports/json-rpc.js:35:26)
    at tryCatcher (/opt/xen-orchestra/node_modules/bluebird/js/release/util.js:16:23)
    at Promise._settlePromiseFromHandler (/opt/xen-orchestra/node_modules/bluebird/js/release/promise.js:547:31)
    at Promise._settlePromise (/opt/xen-orchestra/node_modules/bluebird/js/release/promise.js:604:18)
    at Promise._settlePromise0 (/opt/xen-orchestra/node_modules/bluebird/js/release/promise.js:649:10)
    at Promise._settlePromises (/opt/xen-orchestra/node_modules/bluebird/js/release/promise.js:729:18)
    at _drainQueueStep (/opt/xen-orchestra/node_modules/bluebird/js/release/async.js:93:12)
    at _drainQueue (/opt/xen-orchestra/node_modules/bluebird/js/release/async.js:86:9)
    at Async._drainQueues (/opt/xen-orchestra/node_modules/bluebird/js/release/async.js:102:5)
    at Immediate.Async.drainQueues (/opt/xen-orchestra/node_modules/bluebird/js/release/async.js:15:14)
    at runCallback (timers.js:810:20)
    at tryOnImmediate (timers.js:768:5)
    at processImmediate [as _immediateCallback] (timers.js:745:5)"
}

With error complaining about VDI missing (which is weird), here is my VM-list:

xe vm-list
uuid ( RO)           : d7d5df9e-7ef0-1884-ba83-afdcf0c432ab
     name-label ( RW): [XO Backup pfSense/XO Backup] Ubuntu Xen Orchestra
    power-state ( RO): halted


uuid ( RO)           : 834f3e6f-a4c1-dfd5-c785-673c00fef3c6
     name-label ( RW): [XO Backup pfSense/XO Backup] pfSense
    power-state ( RO): halted


uuid ( RO)           : 98a8dc5a-66f4-a475-ec2a-3de2df439629
     name-label ( RW): Arch Time Machine
    power-state ( RO): halted


uuid ( RO)           : 3bdafe58-3c3d-daa6-55c5-0151aa17e0ad
     name-label ( RW): Ubuntu Xen Orchestra
    power-state ( RO): running


uuid ( RO)           : f9753f68-3d0e-862a-3912-20f7d5f72e62
     name-label ( RW): pfSense
    power-state ( RO): running


uuid ( RO)           : c2cd974f-c490-8860-6672-df6c57e18421
     name-label ( RW): pfSense_2019-09-28T15:23:41.310Z
    power-state ( RO): halted


uuid ( RO)           : fe7c11c6-07c5-2bb5-d31a-bebc42e41f33
     name-label ( RW): Ubuntu Test
    power-state ( RO): halted


uuid ( RO)           : 4b44b9ea-3da5-7a12-9fbf-d1b150cc8d85
     name-label ( RW): Ubuntu Test
    power-state ( RO): running


uuid ( RO)           : eebbe30a-833d-2268-f8e1-fee1f716a70b
     name-label ( RW): [XO Backup Arch-TM] Arch Time Machine
    power-state ( RO): halted


uuid ( RO)           : 43cbe5ad-0bed-0c41-c301-d924a3b5c809
     name-label ( RW): Ubuntu Test
    power-state ( RO): halted


uuid ( RO)           : 0aa694ad-7db9-5b5d-4047-14b532a0a2fd
     name-label ( RW): [XO Backup XO Delta Backup] Ubuntu Xen Orchestra
    power-state ( RO): halted


uuid ( RO)           : 821490d8-5858-f3d1-4c09-b2271aa85da5
     name-label ( RW): Ubuntu Test
    power-state ( RO): halted


uuid ( RO)           : 8d916a65-47b3-4424-917f-8ac9cf474b3c
     name-label ( RW): Control domain on host: xcp-ng-gohilton
    power-state ( RO): running


uuid ( RO)           : 138f595f-32eb-3bb9-95d6-1adb285c4b6b
     name-label ( RW): [XO Backup NonEssential VM] Ubuntu Test
    power-state ( RO): halted


uuid ( RO)           : 4d480db7-f21c-83d5-7db7-b9a8f07775ea
     name-label ( RW): Ubuntu Test
    power-state ( RO): halted

I tried to boot the VM manually by ID:

#xe vm-start uuid=98a8dc5a-66f4-a475-ec2a-3de2df439629
This operation cannot be performed because the specified VDI could not be found on the storage substrate
sr: 28a8b360-7b1b-58ca-81b6-f907c164ec38 (XCP-ng Tools)
vdi: b1a7a49a-f17c-42ac-af73-4429eb57b07a (Old version of guest-tools.iso)

The only other Arch VM listed is a snapshot:

# xe vm-start uuid=eebbe30a-833d-2268-f8e1-fee1f716a70b
Error code: VM_IS_SNAPSHOT
Error parameters: eebbe30a-833d-2268-f8e1-fee1f716a70b ([XO Backup Arch-TM] Arch Time Machine), start

@flipsidecreations

Thanks for clarification on that issue -- Weird however -- I read through a bunch of those links referenced in your post, and the last post was 2017 which fully described the problem. One of the things in general I hate about github are many tickets are closed without any mention of how the problem was resolved -- or if it wasn't just due to lack of inactivity in the thread. Freenas now dropping package based on this thread information that is almost 3 years old.

Not specifically related -- however FreeNAS is doing away with Netdata I believe in the 11.3 release upcoming -- say there is big memory link when running. I don't have specifics but there development team was pretty adamant about the shortcomings of netdata -- so much so they are dropping it. I find it curious while they are dropping support, xcp-ng is adding support. Any testing for this condition?

I don't know guys --
XO - Ubuntu 18.04
Reinstalled community edition xoa. Same error as everyone states above -- endless spinning at the file select tab.
Clearly I'm not the only one having an issue hear.
What logs specifically are your after?

FWIW -- I had a similar problem with VMs going randomly down -- it wasn't windows but various BSD and Linux VM's. Sometimes they would run a few days, other times they would lock up every other day. Logs didn't help because when the VM locked, logs were not written. I even had the xcp-ng installation lock a few times, although it was usually on of the VMs. I started searching for faulty hardware and eventually SMART tested all the drives and mem86 the RAM. Turns out I had some bad RAM modules which I later RMA'd. With new RAM (after after thoroughly testing it), I haven't had any lock ups. I'm not sure this will help you at all.

@nikade Hey thanks for for the link. I ended up just using a LetsEncrypt cert rather than self signed. I think had to add a DNS host override on my router to associate the Local LAN address of the xo server with the domain name of the server contained in the certificate -- Like 10.0.1.50 ---> xo.example.com. Thanks for pointing me in the right direction on this one.

I'm just curious on using this --- do you have a SSL cert with the server name and are you accessing XO through an address like: https://xoserver.example.com? I'm just curious since my XO server is located at 10.0.1.11 and Chrome states cert is invalid -- since I believe SSL needs to resolve to hostnames and not IP addresses.

Anxiously awaiting this feature!!!