Re: [ovirt-users] 3.6 : Moving the hosted-engine to another storage

2016-07-28 Thread Simone Tiraboschi
On Thu, Jul 28, 2016 at 10:59 AM, Alexis HAUSER
 wrote:
>>Unfortunately we know that migrating from HE to HE is not as simple as
>>from physical to HE:
>>https://bugzilla.redhat.com/show_bug.cgi?id=1240466#c21
>>In general the issue is that the DB backup form the old hosted-engine
>>VM contains a lot of references to the previous hosted-engine env and
>>you cannot simply remove/edit them from the engine since they are lock
>>so you have to manually remove them from the DB which is quite
>>risky/error prone.
>
> This is a bit scaring. In case of issue with engine and trying to recover, it 
> could also happen.

The backup and restore procedure on the same env is well testes, the
issue is simply if you need to restore on a different environment
(it's basically a migration) cause you have to remove all the
references to the old env.

> What other way would you suggest for backing the engine VM and being sure to 
> be able to restore it as it was without errors ? Have you ever tried to 
> backup/restore from rsync ?
> If there are data in the DB written when you're performing it, do you think 
> it can cause issues ? If ovirt-engine service is stopped, is that problem 
> avoided ?

Postgres is transactional so if you do it in the proper way I don't
see issue but stopping the ovirt-engine service will of course help.
But the issue is not that you risk data corruption, the issue is that
when you import a backup of the engine DB to a different env, that
backup says the hosted-engine storage domain is still the old one
since it was that in the previous env and so on and you can simply
edit the hosted-engine strage domain location from the engine itself
since we are preventing it.

>>In the mean time I'd suggest, if feasible, to redeploy a new
>>hosted-engine env and reattach there your storage domains and your
>>hosts.
>>This will imply a downtime.
>
> Ok, I think I'll do that. A downtime isn't a problem right now, as I'm still 
> at a pre-production step. (preparing it for production soon)
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users


Re: [ovirt-users] 3.6 : Moving the hosted-engine to another storage

2016-07-28 Thread Alexis HAUSER
>Unfortunately we know that migrating from HE to HE is not as simple as
>from physical to HE:
>https://bugzilla.redhat.com/show_bug.cgi?id=1240466#c21
>In general the issue is that the DB backup form the old hosted-engine
>VM contains a lot of references to the previous hosted-engine env and
>you cannot simply remove/edit them from the engine since they are lock
>so you have to manually remove them from the DB which is quite
>risky/error prone.

This is a bit scaring. In case of issue with engine and trying to recover, it 
could also happen.

What other way would you suggest for backing the engine VM and being sure to be 
able to restore it as it was without errors ? Have you ever tried to 
backup/restore from rsync ?
If there are data in the DB written when you're performing it, do you think it 
can cause issues ? If ovirt-engine service is stopped, is that problem avoided ?

>In the mean time I'd suggest, if feasible, to redeploy a new
>hosted-engine env and reattach there your storage domains and your
>hosts.
>This will imply a downtime.

Ok, I think I'll do that. A downtime isn't a problem right now, as I'm still at 
a pre-production step. (preparing it for production soon)
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users


Re: [ovirt-users] 3.6 : Moving the hosted-engine to another storage

2016-07-27 Thread Simone Tiraboschi
On Wed, Jul 27, 2016 at 5:38 PM, Nir Soffer  wrote:
> On Wed, Jul 27, 2016 at 3:38 PM, Alexis HAUSER
>  wrote:
>> Hi,
>>
>> I'm currently using an NFS storage for my hosted-engine. However, this NFS 
>> server will be removed soon. I'd like to move the hosted-engine to an iSCSI 
>> storage. How can I proceed ? The options for moving/copying VM disk don't 
>> seem to be available for the hosted engine in the web interface.
>
> Yes, hosted engine has some limitations at this point, mainly all the
> interesting
> features like live storage migration, live snapshots, hot plug/unplug disk are
> not available.
>
> Simone, do we have a simple procedure to move the engine to another storage?

Theoretically you could run engine-backup on the current engine VM,
redeploy from scratch on the new storage domain and before running
engine setup, inject there the backup.
Something like:
http://www.ovirt.org/develop/developer-guide/engine/migrate-to-hosted-engine/

Unfortunately we know that migrating from HE to HE is not as simple as
from physical to HE:
https://bugzilla.redhat.com/show_bug.cgi?id=1240466#c21
In general the issue is that the DB backup form the old hosted-engine
VM contains a lot of references to the previous hosted-engine env and
you cannot simply remove/edit them from the engine since they are lock
so you have to manually remove them from the DB which is quite
risky/error prone.

Improving engine-backup to automatically filter hosted-engine
references is an RFE for 4.1.

In the mean time I'd suggest, if feasible, to redeploy a new
hosted-engine env and reattach there your storage domains and your
hosts.
This will imply a downtime.

> Nir
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users


Re: [ovirt-users] 3.6 : Moving the hosted-engine to another storage

2016-07-27 Thread Nir Soffer
On Wed, Jul 27, 2016 at 3:38 PM, Alexis HAUSER
 wrote:
> Hi,
>
> I'm currently using an NFS storage for my hosted-engine. However, this NFS 
> server will be removed soon. I'd like to move the hosted-engine to an iSCSI 
> storage. How can I proceed ? The options for moving/copying VM disk don't 
> seem to be available for the hosted engine in the web interface.

Yes, hosted engine has some limitations at this point, mainly all the
interesting
features like live storage migration, live snapshots, hot plug/unplug disk are
not available.

Simone, do we have a simple procedure to move the engine to another storage?

Nir
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users


[ovirt-users] 3.6 : Moving the hosted-engine to another storage

2016-07-27 Thread Alexis HAUSER
Hi,

I'm currently using an NFS storage for my hosted-engine. However, this NFS 
server will be removed soon. I'd like to move the hosted-engine to an iSCSI 
storage. How can I proceed ? The options for moving/copying VM disk don't seem 
to be available for the hosted engine in the web interface.
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users