BRRABill's Field Report With XenServer
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@BRRABill said:
@olivier said:
That's pretty much a good illustration.
So in theory best practice would be having very similar hardware.
Yes. That's actually the reason all hypervisors only do things like HA on similar hardware. They won't care if it's running on AMD or Intel CPU, but they wouldn't be able to migrate a VM between the two without at least a reboot.
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Is there a log in XO?
It flashes something up when it does something "like VM copy started", but I don't always see anything else.
Is there a place to checkto see the copy did indeed complete?
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You got tasks visible in the top menu (progress is broken due to a bug in XenServer).
Indeed there is a log in XO, but if you are using the sources, I can't tell where, depends on how you installed it.
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@olivier said:
You got tasks visible in the top menu (progress is broken due to a bug in XenServer).
Is there a way to know a task has completed successfully?
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The task list just near the main menu.
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@olivier said:
The task list just near the main menu.
When I mouse over that, it is greyed out and says "no running tasks".
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So it means none of your host is currently doing "long" async tasks (like exporting or importing a VM)
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@olivier said:
So it means none of your host is currently doing "long" async tasks (like exporting or importing a VM)
I guess what I am looking for is something like XC has with the EVENTS tab...
-> copy from XS1 to XS2 started
-> transferring xyz
-> backup completeIs there anything like that in XO? Otherwise how would you officially know the job completed with no errors?
(If it's not there, I'm going to add it to you new version wihlist thread! )
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"Tasks" are a XAPI object, telling you something happening on your host.
The progress value is broken in all current versions of XenServer (fixed in Dundee).
Making a VM copy is a complex task:
- we start to download chunks on the HTTP export handler of the origin host
- at the same time, we start to upload those chunks (on the fly) on the destination host
Each one of them had their respective tasks (export and import) but they don't "know" we are in fact "streaming" stuff between them (for them, it's more like a classical import or export).
Plus, XAPI is a pain to know when the transfer is finished (we had to use some hacks, because they don't use HTTP standard). Furthermore, we don't have the size of what we are exporting, so we can't "guess" the progress by ourselves.
It could fail on any side (fail export, fail import, for many reasons). So we catch anything we could.
But for now, there is no "XO" tasks, just multiple "XenServer tasks".
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Perhaps I am not asking my question properly.
In XC (which is far less featured than XO in my opinion!), you get the following type of status:
"Succeeded","Copying VM 'XenOrchestra' to 'Copy of XenOrchestra' on SR 'SATA Array'
Copied
Time: 00:00:45","xenserver-1","Mar 29, 2016 3:00 PM"There is no way to see that in XO? I can use XC for this, but XO is so much nicer to use, being web-based.
Also, XC seems to have a progress bar that worked when I did this copy. Are they working around the bug somehow?
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@BRRABill Can you provide a real world example with a XC screenshot?
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This is the XenServer task list. Is the task stays at "Success" when it's done? (eg with the migration?)
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@olivier said:
This is the XenServer task list. Is the task stays at "Success" when it's done? (eg with the migration?)
Yes, it stays at success when it is done, with the amount of time it took.
As it moves along, the progress bar there also moves.
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@BRRABill Okay so the only difference with us is they keep ended tasks for a time (how much time?)
About the progress: XenCenter uses the pure XML-RPC way of calling XAPI, which is less prone to bugs, but very CPU intensive (I mean, VERY cpu intensive: decoding tons of XML is horrible)
Using JSON encapsulated in XML-RPC made a small difference for larger infrastructure, around 250 times faster than the shitty XML (for larger infrastructure). See https://xen-orchestra.com/blog/improving-xen-orchestra-performances/ That's the only way for us to have XO working on infrastructure with 1k VMs or more (the problem starts with 100 VMs)
But sadly, they made mistakes in JSON and it's only fixed in Dundee.
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@olivier said:
@BRRABill Okay so the only difference with us is they keep ended tasks for a time (how much time?)
It disappears when you exit XC.
It would just be nice to be able to check in and see if the task actually finished OK, or finished but with errors, or didn't finish at all.
As it stands now, you really don't know, right?
Is that something that COULD be added? Or is it useless and I"m missing the reason why it's useless? (Which is entirely, entirely possible!)
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Do you have to enable auto-power-on on the pool, before you can do it to individual VMs in XO?
My servers are set to auto-power-on in XO, but do not come back up when XS reboots.
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@BRRABill Yes It could be added, but XAPI tasks are such a mess. We can't be sure about them, but yes it's possible to fetch them and store them somewhere. But it will be only informative and not the "truth".
About auto power on: if you did it with XO, it's normally done in both pool and VM at the same time (see https://xen-orchestra.com/blog/auto-start-vm-on-xenserver-boot/ ).
To check your current pool status with autopower on:
xe pool-param-get uuid=<POOL_UUID> param-name=other-config
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@olivier said:
To check your current pool status with autopower on:
xe pool-param-get uuid=<POOL_UUID> param-name=other-config
This is what that command returned:
cpuid_feature_mask: ffffff7f-ffffffff-ffffffff-ffffffff; memory-ratio-hvm: 0.25; memory-ratio-pv: 0.25