Re: KVM hypervm and HA

[Simon Weller]

So today, we aren't using any a watchdog timer on KVM, but Wido has submitted a 
PR to include one. What that means is that today the VM container has to fail 
before an HA action will be completed. If the VM just kernel panics and doesn't 
have it's own kernel watchdog timer, the Mgmt Server will still believe the VM 
is alive and well.


There is also a lot of work underway to greatly improve the KVM HA overall. A 
good chunk of this has already been merged around IPMI management and control 
of the underling host servers. There is a new proposal currently in development 
that will better handle host failure and force a fencing action to make sure we 
have no chance of data corruption. Today if a host fails and the agent goes 
down hard with it, VMs that were on the host will not be HA'd to another host 
until an operator takes an action to remove that host from ACS.


- Si


From: Audrey Roberto B Baldin <audrey.bal...@unitelco.com.br>
Sent: Wednesday, July 12, 2017 8:28 AM
To: users
Subject: Re: KVM hypervm and HA

Hello Victor,

As far as I tested the HA in KVM, it only get in action if:

i. The computing offer you are using to create the guest VM has the Offer HA 
flag on;
ii. The KVM should crash unexpectedly;

To force a crash you can simulate a kernel panic using the command: echo c > 
/proc/sysrq-trigger.

I had some issues that one KVM agent, for some unknown reason, was 
disconnecting from the orchestrator, although it was working and the guest VM 
were running. In this situation I couldn't do anything with the guests VMs 
(move, reload, shutdown) and the HA didn't work.

Hope you find this information useful.

Regards,
Audrey

- Mensagem original -
De: "Ivan Kudryavtsev" <kudryavtsev...@bw-sw.com>
Para: "victor" <vic...@ihnetworks.com>
Cc: "users" <users@cloudstack.apache.org>
Enviadas: Quarta-feira, 12 de julho de 2017 6:55:00
Assunto: Re: KVM hypervm and HA

You should mark VM service offering as HA-enabled and ACS will start vms
automatically. VR, SSVM, CP VMs are also started automatically as needed.

2017-07-12 16:53 GMT+07:00 victor <vic...@ihnetworks.com>:

> Hello,
>
> Thanks for the update.  When a single vm in "hypervm1" is stopped or down,
> it gets automatically started in the second vm. But when the entire
> hypervm1 server  is down completely, the vm' inside it is not getting
> started in the secondary "hypervm2". Is the feature is version specific.
>
> Regards
> Victor
>
>
> On 07/12/2017 08:26 AM, Ivan Kudryavtsev wrote:
>
>> Hi, Victor. They both will be moved automatically to a new host by ACS.
>>
>> 12 июл. 2017 г. 5:23 пользователь "victor" <vic...@ihnetworks.com>
>> написал:
>>
>> Hello,
>>>
>>>   I have a cloudstack system with one management server, one nfs server
>>> and
>>> two kvm hypervm host servers. Initially I configured cloudstack  with
>>> hypervm1, so the system vm  and console proxy gets created in it. Lately
>>> I
>>> have added hypervm2 and created few instances in it. So my doubt is the
>>> following.
>>>
>>> 
>>>
>>> 1, If hypervm 1 is down which contain system-vm,console-proxy and
>>> router-vm, then what will happen.
>>>
>>> 2, If hypervm 1 is down completely and we couldn't make it up, will the
>>> system vm,console proxy and router vm will be switched to hypervm2
>>> automatically.  If it is not automatically, then is there any option for
>>> that.
>>>
>>> 
>>>
>>> Regards
>>>
>>> Victor
>>>
>>>
>>>
>


--
With best regards, Ivan Kudryavtsev
Bitworks Software, Ltd.
Cell: +7-923-414-1515
WWW: http://bitworks.software/ <http://bw-sw.com/>
DESIGN AND DEVELOPMENT OF COMPREHENSIVE SOFTWARE SYSTEMS 
...<http://bitworks.software/>
bitworks.software
design and development of comprehensive software systems for fast-growing 
businesses

Re: KVM hypervm and HA

[Audrey Roberto B Baldin]

Hello Victor,

As far as I tested the HA in KVM, it only get in action if:

i. The computing offer you are using to create the guest VM has the Offer HA 
flag on;
ii. The KVM should crash unexpectedly;

To force a crash you can simulate a kernel panic using the command: echo c > 
/proc/sysrq-trigger.

I had some issues that one KVM agent, for some unknown reason, was 
disconnecting from the orchestrator, although it was working and the guest VM 
were running. In this situation I couldn't do anything with the guests VMs 
(move, reload, shutdown) and the HA didn't work.

Hope you find this information useful.

Regards,
Audrey

- Mensagem original -
De: "Ivan Kudryavtsev" <kudryavtsev...@bw-sw.com>
Para: "victor" <vic...@ihnetworks.com>
Cc: "users" <users@cloudstack.apache.org>
Enviadas: Quarta-feira, 12 de julho de 2017 6:55:00
Assunto: Re: KVM hypervm and HA

You should mark VM service offering as HA-enabled and ACS will start vms
automatically. VR, SSVM, CP VMs are also started automatically as needed.

2017-07-12 16:53 GMT+07:00 victor <vic...@ihnetworks.com>:

> Hello,
>
> Thanks for the update.  When a single vm in "hypervm1" is stopped or down,
> it gets automatically started in the second vm. But when the entire
> hypervm1 server  is down completely, the vm' inside it is not getting
> started in the secondary "hypervm2". Is the feature is version specific.
>
> Regards
> Victor
>
>
> On 07/12/2017 08:26 AM, Ivan Kudryavtsev wrote:
>
>> Hi, Victor. They both will be moved automatically to a new host by ACS.
>>
>> 12 июл. 2017 г. 5:23 пользователь "victor" <vic...@ihnetworks.com>
>> написал:
>>
>> Hello,
>>>
>>>   I have a cloudstack system with one management server, one nfs server
>>> and
>>> two kvm hypervm host servers. Initially I configured cloudstack  with
>>> hypervm1, so the system vm  and console proxy gets created in it. Lately
>>> I
>>> have added hypervm2 and created few instances in it. So my doubt is the
>>> following.
>>>
>>> 
>>>
>>> 1, If hypervm 1 is down which contain system-vm,console-proxy and
>>> router-vm, then what will happen.
>>>
>>> 2, If hypervm 1 is down completely and we couldn't make it up, will the
>>> system vm,console proxy and router vm will be switched to hypervm2
>>> automatically.  If it is not automatically, then is there any option for
>>> that.
>>>
>>> 
>>>
>>> Regards
>>>
>>> Victor
>>>
>>>
>>>
>


-- 
With best regards, Ivan Kudryavtsev
Bitworks Software, Ltd.
Cell: +7-923-414-1515
WWW: http://bitworks.software/ <http://bw-sw.com/>

Re: KVM hypervm and HA

[Ivan Kudryavtsev]

You should mark VM service offering as HA-enabled and ACS will start vms
automatically. VR, SSVM, CP VMs are also started automatically as needed.

2017-07-12 16:53 GMT+07:00 victor :

> Hello,
>
> Thanks for the update.  When a single vm in "hypervm1" is stopped or down,
> it gets automatically started in the second vm. But when the entire
> hypervm1 server  is down completely, the vm' inside it is not getting
> started in the secondary "hypervm2". Is the feature is version specific.
>
> Regards
> Victor
>
>
> On 07/12/2017 08:26 AM, Ivan Kudryavtsev wrote:
>
>> Hi, Victor. They both will be moved automatically to a new host by ACS.
>>
>> 12 июл. 2017 г. 5:23 пользователь "victor" 
>> написал:
>>
>> Hello,
>>>
>>>   I have a cloudstack system with one management server, one nfs server
>>> and
>>> two kvm hypervm host servers. Initially I configured cloudstack  with
>>> hypervm1, so the system vm  and console proxy gets created in it. Lately
>>> I
>>> have added hypervm2 and created few instances in it. So my doubt is the
>>> following.
>>>
>>> 
>>>
>>> 1, If hypervm 1 is down which contain system-vm,console-proxy and
>>> router-vm, then what will happen.
>>>
>>> 2, If hypervm 1 is down completely and we couldn't make it up, will the
>>> system vm,console proxy and router vm will be switched to hypervm2
>>> automatically.  If it is not automatically, then is there any option for
>>> that.
>>>
>>> 
>>>
>>> Regards
>>>
>>> Victor
>>>
>>>
>>>
>


-- 
With best regards, Ivan Kudryavtsev
Bitworks Software, Ltd.
Cell: +7-923-414-1515
WWW: http://bitworks.software/ 

Re: KVM hypervm and HA

[victor]

Hello,

Thanks for the update.  When a single vm in "hypervm1" is stopped or 
down, it gets automatically started in the second vm. But when the 
entire hypervm1 server  is down completely, the vm' inside it is not 
getting started in the secondary "hypervm2". Is the feature is version 
specific.


Regards
Victor

On 07/12/2017 08:26 AM, Ivan Kudryavtsev wrote:

Hi, Victor. They both will be moved automatically to a new host by ACS.

12 июл. 2017 г. 5:23 пользователь "victor"  написал:


Hello,

  I have a cloudstack system with one management server, one nfs server and
two kvm hypervm host servers. Initially I configured cloudstack  with
hypervm1, so the system vm  and console proxy gets created in it. Lately I
have added hypervm2 and created few instances in it. So my doubt is the
following.



1, If hypervm 1 is down which contain system-vm,console-proxy and
router-vm, then what will happen.

2, If hypervm 1 is down completely and we couldn't make it up, will the
system vm,console proxy and router vm will be switched to hypervm2
automatically.  If it is not automatically, then is there any option for
that.



Regards

Victor

Re: KVM hypervm and HA

[Ivan Kudryavtsev]

Hi, Victor. They both will be moved automatically to a new host by ACS.

12 июл. 2017 г. 5:23 пользователь "victor"  написал:

> Hello,
>
>  I have a cloudstack system with one management server, one nfs server and
> two kvm hypervm host servers. Initially I configured cloudstack  with
> hypervm1, so the system vm  and console proxy gets created in it. Lately I
> have added hypervm2 and created few instances in it. So my doubt is the
> following.
>
> 
>
> 1, If hypervm 1 is down which contain system-vm,console-proxy and
> router-vm, then what will happen.
>
> 2, If hypervm 1 is down completely and we couldn't make it up, will the
> system vm,console proxy and router vm will be switched to hypervm2
> automatically.  If it is not automatically, then is there any option for
> that.
>
> 
>
> Regards
>
> Victor
>
>

KVM hypervm and HA

[victor]

Hello,

 I have a cloudstack system with one management server, one nfs server 
and two kvm hypervm host servers. Initially I configured cloudstack  
with hypervm1, so the system vm  and console proxy gets created in it. 
Lately I have added hypervm2 and created few instances in it. So my 
doubt is the following.




1, If hypervm 1 is down which contain system-vm,console-proxy and 
router-vm, then what will happen.


2, If hypervm 1 is down completely and we couldn't make it up, will the 
system vm,console proxy and router vm will be switched to hypervm2 
automatically.  If it is not automatically, then is there any option for 
that.




Regards

Victor