Bug 1241149

Summary: [RFE] Provide way to preform in-cluster upgrade of hosts from el6->el7.
Product: Red Hat Enterprise Virtualization Manager Reporter: Yaniv Lavi <ylavi>
Component: ovirt-engineAssignee: Roman Mohr <rmohr>
Status: CLOSED ERRATA QA Contact: Artyom <alukiano>
Severity: high Docs Contact:
Priority: high    
Version: 3.6.0CC: amarchuk, cshao, dfediuck, dmoessne, eedri, fdeutsch, gklein, jentrena, juwu, lbopf, ldelouw, leiwang, lpeer, lsurette, mavital, mgoldboi, michal.skrivanek, mtessun, nsednev, pablo.iranzo, pdwyer, rbalakri, rgolan, Rhev-m-bugs, rmohr, sauchter, s.kieske, srevivo, ycui, ykaul
Target Milestone: ovirt-3.6.6Keywords: FutureFeature, Improvement, Triaged
Target Release: 3.6.6   
Hardware: Unspecified   
OS: Unspecified   
URL: https://www.ovirt.org/feature/inclusterupgrade
Whiteboard:
Fixed In Version: Doc Type: Enhancement
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2016-06-13 10:38:00 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: SLA RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 1301447    

Description Yaniv Lavi 2015-07-08 14:55:14 UTC
Description of problem:
From 3.6 customer will start moving production environment from el6 to el7 either via upgrade or reinstall. We need to enable adding el7 hosts in that situation and only allow VMs to migrate from el6 to el7 and not back. Then customer can start re-provisioning  hosts and not need to create new cluster and move hosts that can be a risk to the VMs.

Comment 4 Yaniv Lavi 2015-08-09 08:16:07 UTC
This is critical to existing customers looking to upgrade to 3.6. Made this request more general to allow engineering to suggest any design that will allow this.

Comment 5 Michal Skrivanek 2015-08-21 14:24:28 UTC
(In reply to Yaniv Dary from comment #4)
> This is critical to existing customers looking to upgrade to 3.6. Made this
> request more general to allow engineering to suggest any design that will
> allow this.

in 3.5 we decided that the way to upgrade is via a new cluster and cross-cluster one way migration.
How could this be critical?

Comment 6 Julio Entrena Perez 2015-08-21 14:32:56 UTC
(In reply to Michal Skrivanek from comment #5)
> How could this be critical?

The current approach implies:
- creating a new additional cluster for each already existing cluster.
- configuring each new cluster with the same settings (memory optimization, cluster policy, etc) as in the corresponding "old" cluster.
- apply the same permissions to the new clusters as in the old clusters.

Some customers have hundreds of clusters.

Comment 7 Michal Skrivanek 2015-08-21 14:41:59 UTC
(In reply to Julio Entrena Perez from comment #6)
> (In reply to Michal Skrivanek from comment #5)
> > How could this be critical?
> 
> The current approach implies:
> - creating a new additional cluster for each already existing cluster.

not for each, it can be only one new cluster for the duration of conversion.
And since you anyway don't want to keep the empty old cluster around once all hosts from that cluster are upgraded, you can move hosts back to the original cluster (once all el6 hosts are gone, the first el7 host added will make it a el7 cluster)

> - configuring each new cluster with the same settings (memory optimization,
> cluster policy, etc) as in the corresponding "old" cluster.

for the conversion, yes, it indeed should be the same....but it depends on the scale. When the upgrade is fast (small environment, few hosts in cluster) you may not need 1:1 functionality, especially when you don't have extra set of hosts you will be running in degraded mode anyway (some hosts old, some new - without a way how to load-balance the load)

> - apply the same permissions to the new clusters as in the old clusters.
> 
> Some customers have hundreds of clusters.

then it really depends on strategy of the upgrade. small cluster would imply just few hosts in each, so you anyway need to upgrade carefully one by one with respect to the load.

Comment 20 Roman Mohr 2015-12-18 10:28:36 UTC
State of development can be followed on the feature page:

http://www.ovirt.org/Features/InClusterUpgrade#InClusterUpgrade

Comment 21 Roman Mohr 2016-02-23 10:27:35 UTC
Wiki page is now at www.ovirt.org/feature/inclusterupgrade

Comment 22 Roy Golan 2016-03-20 08:40:43 UTC
Hi Jullie,

This important process should go into the user-guide I believe. We have this wiki from comment 21 to start from. Let me know of any think you need.

Thanks

Comment 23 Julie 2016-03-20 23:12:30 UTC
Hi Roy,
 We have a docs bug to track this change (BZ#1301447). It should affect the standard upgrade procedure in the Upgrade Guide[1] and the self-hosted engine upgrade procedure in the SHE Guide[2].

[1] https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Virtualization/3.6/html/Upgrade_Guide/Upgrading_a_Red_Hat_Enterprise_Linux_6_Cluster_to_Red_Hat_Enterprise_Linux_7.html
[2] https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Virtualization/3.6/html/Self-Hosted_Engine_Guide/Upgrading_the_Self-Hosted_Engine_from_6_to_7.html

Kind regards,
Julie

Comment 24 Mike McCune 2016-03-28 23:29:58 UTC
This bug was accidentally moved from POST to MODIFIED via an error in automation, please see mmccune with any questions

Comment 25 Artyom 2016-05-01 08:08:08 UTC
Verified on rhevm-3.6.6-0.1.el6.noarch
See polarion run: https://polarion.engineering.redhat.com/polarion/#/project/RHEVM3/testrun?id=3%5F6%5FSLA%5FIn%5FCluster%5FUpgrade%5Frun%5F1

Comment 31 Eyal Edri 2016-06-19 12:57:28 UTC
Please clone bug or fix flags.