Bug 1290340 - [RFE] RHEV-H el6 to el7 in-cluster migration
Summary: [RFE] RHEV-H el6 to el7 in-cluster migration
Keywords:
Status: CLOSED DUPLICATE of bug 1421098
Alias: None
Product: ovirt-node
Classification: oVirt
Component: RFEs
Version: 3.6
Hardware: Unspecified
OS: Unspecified
high
high
Target Milestone: ovirt-4.2.0
: ---
Assignee: Douglas Schilling Landgraf
QA Contact: Huijuan Zhao
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2015-12-10 09:35 UTC by Fabian Deutsch
Modified: 2017-04-11 07:35 UTC (History)
15 users (show)

Fixed In Version:
Doc Type: Enhancement
Doc Text:
Clone Of:
Environment:
Last Closed: 2017-04-11 07:35:14 UTC
oVirt Team: Node
Embargoed:
fdeutsch: ovirt-4.2?
mgoldboi: planning_ack+
rule-engine: devel_ack?
ycui: testing_ack+


Attachments (Terms of Use)
audit (154.42 KB, text/plain)
2016-03-29 11:01 UTC, Huijuan Zhao
no flags Details
log (6.81 MB, application/x-gzip)
2016-03-31 06:43 UTC, Huijuan Zhao
no flags Details

Description Fabian Deutsch 2015-12-10 09:35:35 UTC
Description of problem:
Currently it is not possible to update a Node el6 host to Node el7 host.
The problem is that all host specific configuration is lost.

To prevent this, a mechnism is needed to perform major version upgrades.

Comment 1 Fabian Deutsch 2015-12-10 09:41:25 UTC
Rough idea:

1. Install 3.5 el6
2. Register to engine 3.6
3. Add host to 3.5 compat cluster
4. Check that everything is working
5. Put host into maintenance mode

6. On the host: Save the contents of /config (i.e. create tarball and copy to other host)

7. Reinstall host with 3.6 el7 (don't register)

8. Boot into host, unmount all files from /config
9. On the host: Empty /config, restore /config from tarball from step 6

10. Reboot host with permissive mode
11. On the host: restorecon -r / (warnings are okay)

12. Activate host in Engine
13. Check that everything is working

14. rescude audit.log

Comment 3 Ying Cui 2015-12-10 09:46:59 UTC
Also need to consider
In the same cluster, there probably have more than one Node 6 hosts, most of the situation is this, and Node 6 and Node 7 can not be in same cluster in RHEV-M.

Comment 4 Fabian Deutsch 2015-12-10 10:00:20 UTC
Yes, that also needs to be considered.

Maybe it's even viable to say:

1. Start wtih all hosts in cluster A (el6)
2. For each host: Update (as in comment 1) and move to cluster B (el7)

Comment 6 Fabian Deutsch 2015-12-17 08:23:49 UTC
This will be a migration, not an upgrade, thus there will be no way to roll back.

However, a rollback is possibly, to reinstall with the old el6 image again, and restore the saved config there.

Also: We can only do this with reinstall, because the partition sizes differ between el6 and el7.

Comment 7 Red Hat Bugzilla Rules Engine 2016-01-21 23:04:40 UTC
Bug tickets must have version flags set prior to targeting them to a release. Please ask maintainer to set the correct version flags and only then set the target milestone.

Comment 8 Red Hat Bugzilla Rules Engine 2016-01-21 23:04:40 UTC
Target release should be placed once a package build is known to fix a issue. Since this bug is not modified, the target version has been reset. Please use target milestone to plan a fix for a oVirt release.

Comment 9 Ying Cui 2016-03-22 07:40:46 UTC
Huijuan, could you give a roughly try according to comment 1 Fabian provided.

Comment 10 Fabian Deutsch 2016-03-24 13:02:29 UTC
Raising priority, because the same flow might be used for vintage to NGN migration

Comment 12 Huijuan Zhao 2016-03-29 11:00:56 UTC
I tried to test this issue according to comment 1, test results are same as expectation in comment 1.

Test version:
RHEVH-6.7-20160219.0.el6ev
RHEVH-7.2-20160328.0.el7ev

Test steps:
1. Install 3.5 el6: RHEVH-6.7-20160219.0.el6ev
2. Register to engine 3.6
3. Add host to 3.5 compat cluster (configure the "Management Network" to "rhevm")
4. Check that everything is working
5. Put host into maintenance mode on rhevm

6. On the host: Save the contents of /config (create config.tar.gz and copy to other host)
7. Reinstall host with 3.6 el7:RHEVH-7.2-20160328.0.el7ev (did not register)

8. Boot into host, unmount all files from /config (rm all files from /config)
9. On the host: Empty /config, restore /config from tarball from step 6

10. Reboot host with permissive mode(add "enforcing=0" in kernel cmdline)
11. On the host: restorecon -r / 
2 failed message:
restorecon set context /dev/.initramfs/live->system_u:object_r:device_t:s0 failed:'Read-only file system'
restorecon set context /sys/fs/cgroup->system_u:object_r:cgroup_t:s0 failed:'Read-only file system'

12. Activate host in Engine
13. Check that everything is working

Additional info:
please refer to the attachment audit for /var/log/audit/audit.log

Comment 13 Huijuan Zhao 2016-03-29 11:01:42 UTC
Created attachment 1141191 [details]
audit

Comment 14 Fabian Deutsch 2016-03-29 11:58:55 UTC
Just to clarify: Everything is working after step 13?

Comment 15 Huijuan Zhao 2016-03-30 02:26:20 UTC
(In reply to Fabian Deutsch from comment #14)
> Just to clarify: Everything is working after step 13?

More accurately, after step 13, the prior(on el6) settings on el7  are all working well(permissive mode):
1. Network/ssh work well (the management network is "rhevm")
2. Host is up in Engine

Additional info:
After step 13, I setup SNMP/CIM/Logging/kdump/RHSM on el7 just now , all have error report, and setup failed.

Comment 16 Fabian Deutsch 2016-03-30 14:33:23 UTC
(In reply to Huijuan Zhao from comment #15)

> Additional info:
> After step 13, I setup SNMP/CIM/Logging/kdump/RHSM on el7 just now , all
> have error report, and setup failed.

For these errors - please provide all the logs.

Comment 17 Huijuan Zhao 2016-03-31 06:43:44 UTC
Created attachment 1142068 [details]
log

Comment 18 Huijuan Zhao 2016-03-31 06:44:57 UTC
(In reply to Fabian Deutsch from comment #16)
> (In reply to Huijuan Zhao from comment #15)
> 
> > Additional info:
> > After step 13, I setup SNMP/CIM/Logging/kdump/RHSM on el7 just now , all
> > have error report, and setup failed.
> 
> For these errors - please provide all the logs.

please refer to the attachment "log" for all the logs, thanks

Comment 19 Fabian Deutsch 2016-03-31 10:15:04 UTC
Huijuan, can we get access to such a host?

Comment 23 Red Hat Bugzilla Rules Engine 2016-05-31 12:37:03 UTC
This request has been proposed for two releases. This is invalid flag usage. The ovirt-future release flag has been cleared. If you wish to change the release flag, you must clear one release flag and then set the other release flag to ?.

Comment 24 Marina Kalinin 2017-04-10 17:57:48 UTC
Guys, do we still care about this bug? since 3.6 does not really matter today. And we have this for RHVH 4.x migration:
https://bugzilla.redhat.com/show_bug.cgi?id=1421098

Comment 25 Huijuan Zhao 2017-04-11 07:17:52 UTC
(In reply to Marina from comment #24)
> Guys, do we still care about this bug? since 3.6 does not really matter
> today. And we have this for RHVH 4.x migration:
> https://bugzilla.redhat.com/show_bug.cgi?id=1421098

Sandro, could you please help to ack this question?
Thanks!

Comment 26 Sandro Bonazzola 2017-04-11 07:35:14 UTC
Agreed, marking this as duplicate of bug #1421098 since the migration to el7 will happen with NGN 3.6

*** This bug has been marked as a duplicate of bug 1421098 ***


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