Re: [ovirt-users] upgrade hosted-engine os ( not hosts )

Op do 30 jun. 2016 om 21:17 schreef Yedidyah Bar David <didi(a)redhat.com&gt;: > > On Thu, Jun 30, 2016 at 9:46 PM, Paul Groeneweg | Pazion <paul(a)pazion.nl&gt; > wrote: > > Things are getting more clear to me, thanks! > > And this whole upgrade is something I should prepare well and not try to > > do > > in a few hours at night :) > > > > Resuming, there are multiple solutions: > > > > 1. upgrade el6 to el7 > > no go => I need to upgrade postgresql and redhat warns about upgrading > > 6.6 > > to 7 because of newer packages > > 2. install a new HE on new Host new storage domain > > a lot of work => I have to turn off VMs, import storage domain into new > > setup and reinstall hosts. > > 3. install a new HE on new Host existing storage domain > > possibly not without issues => I have to manually update references to > > the > > hosted storage or better wait till there is an upgrade tool. > > 4. (re)install HE in current VMS container. > > => I can keep my Hosts and reference to the storage domain. > > > > So I guess my best bet is to go for option 4. > > > > The flow I am planning to follow would be: > > > > 1. Move to global maintenance ( keep VMs running ) > > 2. backup ( I have also a complete disk install of old hosted-engine ) > > 3. reboot with different conf, to boot from cd > > 4. acces console and run install + import the backup in the engine vm > > ? 5. run engine-setup to configure new install with engine restore data > > 6. reboot hosted-engine > > 7. Remove from global maintenance > > 8. launch web gui and I should be able to manage all still running VMs > > again. > > > > Would above be working or am I missing something and I doubt step 5. Is > > this needed? > > Yes. > > In a normal backup/restore flow, it's less important, although officially > it's mandatory. But in above flow, it's not just backup/restore, but also > upgrade from 3.6 to 4.0. > > In principle you can also do all of the above with 3.6, at least inside > the engine, verify that all seems good, then upgrade to 4.0 later. See > also: > > https://bugzilla.redhat.com/1332463 > > But I do not remember reports from people trying it. > Good point, I planned to first get 3.6 running on el7 and from there upgrade hosted-engine to 4.0 ( between step 6 and 7 ). Altough this way I keep old 3.6 files on my fresh installl...what would you advice? directly install 4.0 on new el7 host? ( I am running 3.6.7, so above bug is probably fixed ).

> > One very important thing you did not mention: Try this on a test system, > including rollback to your backup, after you finished everything and > (supposedly) found out something broken. Better safe than sorry :-) A test setup might provide a good practice. But requires extra spare hosts...

I do have a bare metal restore option. So I am able ( with cd boot and console mode) to restore hosted engine within an hour to previous state :-)

Thanks a lot for all info! > > Best, > > > > > Best Regards, > > Paul > > > > > > > > Op do 30 jun. 2016 om 14:44 schreef Simone Tiraboschi > > <stirabos(a)redhat.com&gt;: > >> > >> On Thu, Jun 30, 2016 at 8:34 AM, Paul Groeneweg | Pazion > >> <paul(a)pazion.nl&gt; > >> wrote: > >> > Hi Yedidyah, > >> > > >> > Thank you for the comprehensive answers. > >> > > >> > I think I go for a complete reinstall ( read also OS upgrade tool is > >> > not > >> > adviced on 6.6 or higher as there might be newer packages as on 7 ). > >> > No > >> > doubting to re-use current VM or setup from scratch ( fresh host with > >> > new > >> > hosted-engine and existing storage domein ). > >> > >> If you are planning to redeploy hosted-engien from scratch and > >> restoring on the new engine DB a backup of the previous one, please > >> carefully consider this: > >> https://bugzilla.redhat.com/show_bug.cgi?id=1240466#c21 > >> > >> So, if you choose that path you'll have also to manually remove any > >> reference to the previous hosted-engine from the restored DB. > >> I'd strongly suggest you to wait for the upgrade tool to be fixed > >> since manually doing this upgrade can be really error prone. > >> > >> > You explain the steps ( 1 to 6 ), but then don't talk about storage > >> > domain > >> > import. > >> > Does it mean, when I reinstall the hosted-engine in the current he VM > >> > and > >> > restore an engine-backup ( step 5 ) I am able to start vm from Host > >> > and > >> > it > >> > is still connected to the master storage ( so no need for storage > >> > import) ? > >> > > >> > Best Regards, > >> > Paul Groeneweg > >> > > >> > > >> > Op do 30 jun. 2016 om 08:00 schreef Yedidyah Bar David > >> > <didi(a)redhat.com&gt;: > >> >> > >> >> On Wed, Jun 29, 2016 at 10:07 PM, Paul Groeneweg | Pazion > >> >> <paul(a)pazion.nl&gt; wrote: > >> >> > > >> >> > I am looking for a way to get my hosted-engine running on el7 so I > >> >> > can > >> >> > upgrade to oVirt 4.0. Currently my hosts already run el7, but my > >> >> > hosted-engine is still el6. > >> >> > > >> >> > I read > >> >> > > >> >> > > >> >> > > >> >> > https://www.ovirt.org/documentation/how-to/hosted-engine-host-OS-upgrade/ > >> >> > but this is only about the hosts. > >> >> > > >> >> > I read https://www.ovirt.org/documentation/how-to/hosted-engine/, > >> >> > but > >> >> > it > >> >> > only mentions upgrade of the hosted-engine software, not the OS. > >> >> > > >> >> > I understood I can do a fresh hosted-engine install, and then > >> >> > import > >> >> > my > >> >> > storage domain to the new hosted engine, but: > >> >> > > >> >> > - Do I need to restore my hosted engine database? ( like described > >> >> > here: > >> >> > > >> >> > > >> >> > > >> >> > http://www.ovirt.org/develop/developer-guide/engine/migrate-to-hosted-eng... > >> >> > ) > >> >> > >> >> You might not have to, if you only care about the imported VMs from > >> >> your > >> >> storage. This will not keep other configuration, such as > >> >> users/roles/permissions > >> >> etc. > >> >> > >> >> > - Can I directly install hosted-engine 4.0 and then import the > >> >> > storage > >> >> > domain? Or should I install same hosted-engine version? > >> >> > >> >> AFAIK 4.0 engine can import 3.6 storage domains without problem. > >> >> > >> >> > - Do I first need another master storage domain or can I directly > >> >> > import > >> >> > my > >> >> > old master storage domain? > >> >> > >> >> No idea. Even if you do, you can create a small empty one and later > >> >> remove > >> >> it. > >> >> > >> >> > - When importing the storage domain what is the risk it fails ( I > >> >> > have > >> >> > backups, but it would cost a day to restore all ) > >> >> > >> >> No idea, but IIRC we got many successful reports and at most few > >> >> failures > >> >> for this. > >> >> > >> >> > - How long would import take? few minutes or hours? ( I want to > >> >> > keep > >> >> > down > >> >> > time as low as possible ). > >> >> > >> >> Again no idea. Perhaps do some test? > >> >> > >> >> > > >> >> > Another option would be upgrade the OS ( with redhat-upgrade-tool > >> >> > ) > >> >> > or > >> >> > is > >> >> > this a path for disaster? > >> >> > >> >> Didn't work for us well, so we decided to not support it. If you > >> >> decide > >> >> to > >> >> try, > >> >> make sure you test carefully beforehand. From ovirt's POV: > >> >> 1. You'll need to handle postgresql upgrade. > >> >> 2. Right after OS upgrade, you'll still have (I think) el6 packages > >> >> of the engine. It will hopefully be in a good-enough state for > >> >> upgrade > >> >> to 4.0, but we didn't test this. > >> >> 3. Specifically, if upgrade fails, rollback will most likely not > >> >> work, > >> >> so you'll have to manually handle this - take a full vm backup and > >> >> make > >> >> sure you can restore it. > >> >> > >> >> > > >> >> > I hope someone can tell me how I can smoothly upgrade my > >> >> > hosted-engine > >> >> > up to > >> >> > el7 and run oVirt 4. > >> >> > >> >> We are working on a tool/wizard to help with this process. It used > >> >> to > >> >> work, > >> >> but at some point it was decided that one of the actions it does is > >> >> risky > >> >> and was blocked, thus the tool is broken currently. > >> >> > >> >> You can invoke the tool by running: 'hosted-engine > >> >> --upgrade-appliance'. > >> >> As noted above, this is currently broken. > >> >> > >> >> There are several open bugs about it, e.g.: > >> >> > >> >> https://bugzilla.redhat.com/show_bug.cgi?id=1319457 > >> >> https://bugzilla.redhat.com/show_bug.cgi?id=1343425 > >> >> https://bugzilla.redhat.com/show_bug.cgi?id=1343593 (closed, this is > >> >> what broke the tool) > >> >> > >> >> Basically, you can manually do what the tool is supposed to do: > >> >> 1. Make sure state is clean and stable (no running/pending storage > >> >> actions, > >> >> no VMs in the middle of migration etc), all clusters are compat > >> >> level > >> >> 3.6, > >> >> etc. > >> >> 2. Move to global maintenance > >> >> 3. backup the engine using engine-backup and keep the backup > >> >> elsewhere > >> >> 4. Reinstall engine vm with el7 and 4.0 engine (the tool will use > >> >> the > >> >> engine > >> >> appliance, you might too but not sure how exactly). > >> >> 5. Restore the backup and run engine-setup. > >> >> 6. If all looks ok, leave global maintenance. > >> >> > >> >> If you manually keep a full backup of the engine vm before step 4, > >> >> you might be able to restore this backup if there are problems. > >> >> Doing this in the provided tool is currently the main blocking issue > >> >> for it. Hopefully will be provided in 4.0.1. > >> >> > >> >> Best, > >> >> -- > >> >> Didi > >> > > >> > > >> > _______________________________________________ > >> > Users mailing list > >> > Users(a)ovirt.org > >> > http://lists.ovirt.org/mailman/listinfo/users > >> > > > > > -- > Didi