[ovirt-users] Misc architecture questions

[Sandro Bonazzola]

Il 23/07/2014 00:09, Itamar Heim ha scritto:
> On 07/17/2014 11:14 AM, Maël Lavault wrote:
>> Hi,
>>
>> I'm a student currently doing my final study project based around Ovirt.
>>
>> I played a lot with Ovirt to have an overview of what could or could not
>> be done, but I still have a few questions and stuff I want to clarify.
>>
>> My project consist of a HA architecture using Ovirt, powered by 8
>> reasonably powerful servers (4 x Quad core Opteron, 32Go RAM, 2x10k RPM
>> HDD) equipped with 2 NIC each.
>>
>> I followed this tutorial to use Ovirt with GlusterFS :
>>
>> http://community.redhat.com/blog/2014/05/ovirt-3-4-glusterized/
>>
>> Worked well !
>>
>> I installed 2 self hosted engine on 2 different servers and a GlusterFS
>> using 2 other servers.
>>
>> But since we had only 2 x 1Gb NIC per server, we decided to go with
>> bonding and VLAN to separate each networks inspired by this blog post :
>>
>> http://captainkvm.com/2013/04/maximizing-your-10gb-ethernet-in-rhev/
>>
>> Unfortunately, it seems like Ovirt 3.4 does not support installing
>> self-hosted engine on bond + vlan. I tried 3.5 but there were to much
>> bug to be usable and the project is set to be deployed in 2 months.
> 
> should be available via:
> http://gerrit.ovirt.org/#/c/29730/
> ?

Yes, it's available in 3.4.3[1]. However, looks like VDSM has some issue with the network [2][3]
So in order to use it you need to downgrade vdsm to previous version by calling
 # yum downgrade "vdsm*"
We're waiting a new build of vdsm packages fixing the issues.


[1] http://www.ovirt.org/OVirt_3.4.3_Release_Notes#oVirt_Hosted_Engine_Setup
[2] https://bugzilla.redhat.com/show_bug.cgi?id=1121145
[3] https://bugzilla.redhat.com/show_bug.cgi?id=1121643

> 
>>
>> A colleague suggested me a workaround using OpenvSwitch between Ovirt
>> and NIC bond to "translate tagged packet into non tagged packet" and
>> hide the bond from Ovirt. Does this have a chance to work ?
>>
>> Since the GlusterFS is accessed by NFS, I was able to bond the two
>> servers.
>>
>> A few questions :
>>
>> - What is the purpose of ovirtmgmt network ? I did a lot of search by
>> haven't found any clear explanation. Does it need to be publicly
>> accessible or a private ip is fine too ?
> 
> just what engine used to communicate to hosts.
> also, by default, the display network and vm network.
> 
>>
>> - Is the display network used for SPICE/VNC connection ?
> 
> yes.
> 
>>
>> - How do Ovirt differentiate VM network from a storage network ? They
>> both have the same vm role in the interface. Both networks could
>> (should) be on private ip range right ?
> 
> that depends on you deploying them on different networks?
> 
>>
>> - How can I add the storage network after (or before, would be better)
>> self hosted engine is installed ? (Since self hosted engine is stored on
>> Gluster, I will loose connection to the engine)
> 
> configure it on host B. move hosted engine to host B. configure it on host A?
> 
>>
>> - Using self hosted engine, does all my nodes need to be installed with
>> hosted-engine --deploy, or can I have only 2 self hosted engine nodes
>> and 4 classic nodes ?
> 
> you can have 2 self hosted and 50 classic nodes as well.
> no need to match hosted engine to the entire cluster (nor is hosted engine tested with being deployed on 50 hosts...)
> 
>>
>> - I'm trying to cleanly re-install the second hosted engine after some
>> experiments, but the behavior is strange :
>>
>> [ INFO  ] Stage: Transaction commit
>> [ INFO  ] Stage: Closing up
>>            To continue make a selection from the options below:
>>            (1) Continue setup - engine installation is complete
>>            (2) Power off and restart the VM
>>            (3) Abort setup
>> Isn't this supposed to give me information to connect to the vm so i can
>> install the engine ?
>
> sandro/didi?

if this is the install on the second host, you can just answer 1 and go on.
We've a bug opened [4] about this issue, setup should assume here that the engine is up and running without any question.

[4] https://bugzilla.redhat.com/show_bug.cgi?id=1106561


> 
> 
> 
>>
>> Thanks a lot for this truly well made software !
> 
> thank you for using it.

thank you for using it.

> 
> 
>>
>>
>> _______________________________________________
>> Users mailing list
>> Users at ovirt.org
>> http://lists.ovirt.org/mailman/listinfo/users
>>
> 


-- 
Sandro Bonazzola
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