XOA Unable to connect xo server every 30s

[Danp]

Hi Jerry,

I believe that we had similar reports when XO6 was first releases, but I don't recall seeing this recently. We can assist you in troubleshooting this issue if you open a support ticket and provide access via the support tunnel.

Regards, Dan

[jerry1333]

Support tunnel is active but I have troubles to access support "Oops, something went wrong! Don't worry, our team is already on it".

I'll keep trying, thanks.

[poddingue]

Good news, or at least, that's my understanding.
This was a known bug and it's fixed in XO 6.4 (released April 29, PR #9681). Upgrading should make those alerts disappear for good. Thanks for the video, it made the report unambiguous.

[GregBinSD]

@jerry1333 @poddingue

First of all, XO and XCP-ng are running very well on all hosts and VMs, and I am using XO-5 without any issues.

I have been noticing the same exact issue jerry1333 had, or may still have, with an annoying message that appears just after 30 seconds of connecting to the Xen Orchestra version 6 initial home screen with a Chrome browser (version 153) on my Windows 11 PC. In the past, the error message at the top of the window used to cycle on and off, over and over every 30 seconds. Now, if I don't click on "Retry", the "Unable to connect" message remains indefinitely.

Xen Orchestra is up to date: Master, commit fc571

I consider this to be a mere annoyance, but if I am the only one experiencing this, perhaps someone can give me a suggestion on where to look for a solution.

Thank you.

[GregBinSD]

Here are two more notes regarding the XO6 "Unable to connect to XO server. Retry" message, which pops up after 30 seconds.

It occurs when either the Chrome or the Microsoft Edge browsers are used on my Windows 11 PC.

However, I often use a Samsung Tab-A9 (tablet), and it does not have this issue with XO6. It uses the Chrome browser.

[john.c]

@GregBinSD said:

Here are two more notes regarding the XO6 "Unable to connect to XO server. Retry" message, which pops up after 30 seconds.

It occurs when either the Chrome or the Microsoft Edge browsers are used on my Windows 11 PC.

However, I often use a Samsung Tab-A9 (tablet), and it does not have this issue with XO6. It uses the Chrome browser.

To enlighten you the Microsoft Edge your talking about is not the original release (from Windows 10). It’s the Chromium based release from during Windows 10 and has been that one ever since. The original release of Microsoft Edge had its own rendering engine called MSHTML. The current modern Edge effectively shares a common upstream code base with Google Chrome, namely Chromium.

The Samsung Tab-A9 doesn’t have the issue even though it, uses the same browser namely Google Chrome. This is the case because the tablet uses a version of Google Android, which has its own kernel, which is a fork or variation of the Linux Kernel.

[GregBinSD]

@john.c @poddingue
I am very happy to report that I am no longer receiving the "XOA Unable to connect xo server every 30s" message on the Chrome browser of my Windows 11 PC, as of today, after updating the XO-CE VM and all xcp-ng hosts.

I just updated the XO-CE VM to master, commit 70b08, and ran a rolling pool update of my 3 xcp-ng hosts.

Thank you to the Vates team.

[cocoon]

Just as an addition, as I still had it with current code from main and found out what is going on.

The cause can simply be a wrong time on the XO Server.

The fix here simply extends the time drift, but if your server is more out of sync than this value, you will always see the error:
https://github.com/vatesfr/xen-orchestra/pull/9681/changes

Can be made more visible in code with this change:

File: xen-orchestra/@xen-orchestra/web-core/lib/packages/remote-resource/sse.store.ts

  //const hasErrorSse = computed(() => isError.value || sse.value.errorSse !== null)

  const hasErrorSse = computed(() => {
    const result = isError.value || sse.value.errorSse !== null
  
    if (result) {
      console.error('[XO SSE STATE]', {
        isError: isError.value,
        lastPing: sse.value.lastPing,
        now: now.value.getTime(),
        difference: sse.value.lastPing
          ? now.value.getTime() - sse.value.lastPing
          : null,
        errorSse: sse.value.errorSse,
      })
    }
  
    return result
  })
  
  const isConnected = computed(() => sse.value.id !== undefined)

[olivierlambert]

Ping @poddingue

[poddingue]

Thanks @cocoon, and I owe a correction: when I said in https://xcp-ng.org/forum/post/104865 that 6.4 would make these alerts disappear for good, I overstated it.

If I'm reading the code right this time, the XO server sends a ping every 30 seconds stamped with its own clock (https://github.com/vatesfr/xen-orchestra/blob/master/@xen-orchestra/rest-api/src/events/event.class.mts), and the browser compares that stamp with its own clock and shows the banner once the gap passes 40 seconds (https://github.com/vatesfr/xen-orchestra/blob/master/@xen-orchestra/web-core/lib/packages/remote-resource/sse.store.ts).

So https://github.com/vatesfr/xen-orchestra/pull/9681 widened the margin from 32 to 40 seconds, but a browser whose clock runs ahead of the XO server by more than about 10 seconds would still see it.

That might be why @GregBinSD saw it on the Windows PC and not on the tablet, though that's only a guess on my part. I'll pass this on to the XO team, since comparing two different clocks looks fragile to me, but they'll know far better than I do whether there's a reason it's done that way.