On Mon, Nov 11, 2019 at 12:26 PM Staniforth, Paul <P.Staniforth@leedsbeckett.ac.uk> wrote:

Thanks, I should have been clearer, what I meant was could you install 4.3.5 and restore to that, then run engine-setup --offline?

Of course, this should work. The only point is that once 4.3.6 is released, it's not that easy to install 4.3.5, because yum generally tries to install the latest versions of stuff - and in theory, there might be issues with installing stuff from 4.3.6 repo with a 4.3.5 engine, so if you want an exact replicate of a 4.3.5 engine, you have to check all relevant packages, not just the engine.

Regards, Paul S. ________________________________ From: Yedidyah Bar David <didi@redhat.com> Sent: 11 November 2019 10:19 To: Staniforth, Paul <P.Staniforth@leedsbeckett.ac.uk> Cc: wangyu13476969128@126.com <wangyu13476969128@126.com>; users <users@ovirt.org> Subject: Re: [ovirt-users] Re: After importing the ovirt-engine 4.3.5 backup file into ovirt-engine 4.3.6, will the information of the ovirt-engine 4.3.6 management interface be the same as ovirt-engine 4.3.5?

On Mon, Nov 11, 2019 at 12:12 PM Staniforth, Paul <P.Staniforth@leedsbeckett.ac.uk> wrote:

...

I haven't tried it but doesn't engine-setup --offline stop it upgrading minor releases.

It prevents only the packager component.

If you already have 4.3.6 installed, which was the original question, then engine-setup will still update the database schema. And if it didn't, the 4.3.6 engine might fail working correctly with a 3.4.5.5 database. In particular:

The documentation for engine-backup always stated that you must run engine-setup immediately after restore. But at some points in time, and under certain conditions, this was actually optional. You could have done a restore, and immediately start the engine, and it would have worked. But this isn't the case if your restored db is older than the installed engine. Then, you must run engine-setup before starting the engine.

Best regards,

...

Regards, Paul S. ________________________________ From: Yedidyah Bar David <didi@redhat.com> Sent: 11 November 2019 07:57 To: wangyu13476969128@126.com <wangyu13476969128@126.com> Cc: users <users@ovirt.org> Subject: [ovirt-users] Re: After importing the ovirt-engine 4.3.5 backup file into ovirt-engine 4.3.6, will the information of the ovirt-engine 4.3.6 management interface be the same as ovirt-engine 4.3.5?

On Tue, Oct 29, 2019 at 11:55 AM <wangyu13476969128@126.com> wrote:

...

The current version of ovirt-engine in production environment is 4.3.5.5. In order to prevent the ovirt-engine machine from being down, the management interface cannot be used, according to the relevant link: https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fovirt.org%...

I backed it up using the command: engine-backup --scope=all --mode=backup --file=file_name --log=log_file_name

I have prepared another machine as a spare machine. Once the ovirt-engine is down in the production environment, the standby machine can be UP and the standby machine can manage the ovirt-nodes.

According to the relevant links: https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fovirt.org%...

The ovirt-engine is installed on the standby machine.

After I have executed these three commands: 1. yum install https://eur02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fresources.o...

2. yum update

3. yum install ovirt-engine

I found that the ovirt-engine version of the standby machine is 4.3.6

So my question is:

1. The ovirt-engine version of the standby machine is 4.3.6, and the production environment ovirt-engine version is 4.3.5.5, which command is used on the production environment ovirt-engine machine: engine-backup --scope=all --mode=backup --file=file_name --log=log_file_name

Files obtained after using the backup command on the ovirt-engine in the production environment are restored using these two files under the standby computer. Will the information on the ovirt-engine management interface of the standby computer be consistent with the ovirt-engine of the production environment (eg data center, host, virtual machine, etc.)?

In principle it should be ok. After you restore with above command, you should run 'engine-setup', and this will update your restored database schema to 4.3.6. This is not routinely tested explicitly, though, but I expect that people often do this, perhaps even unknowingly, when they restore from a backup taken with a somewhat-old version.

...

2. Can the ovirt-engine of the standby machine be installed with version 4.3.5.5? How do I need to modify the following three commands to get the backup machine to install the version 4.3.5.5? 1. yum install https://eur02.safelinks.protection.outlook.com/?url=http%3A%2F%2Fresources.o... 2. yum update 3. yum install ovirt-engine

In theory you can change last one to 'yum install ovirt-engine-4.3.5.5'. I didn't try that, and you are quite likely to run into complex dependencies you'll have to satisfy by yourself.

I think the best solution for you, if you care about active and standby to be identical, is to upgrade your active one as well, and keep them same version going forward.

I'd also like to note that maintaining a standby engine and using it the way you intend to, is not in the scope of oVirt. People do similar things, but have to manually work around this and be careful. One very important issue is that if for any reason you allow both of them to be up at the same time, and manage the same hosts, they will not know about each other, and you'll see lots of confusion and errors.

You might also want to check:

1. Hosted-engine setup with more than one host as hosted-engine host. There, you only have a single engine vm, but it can run on any of your hosts. You still have a single VM disk/image, and if that's corrupted, you have no HA and have to somehow reinstall/restore/etc.

2. https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.ovirt....

Best regards, -- Didi _______________________________________________ Users mailing list -- users@ovirt.org To unsubscribe send an email to users-leave@ovirt.org Privacy Statement: https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.ovirt.... oVirt Code of Conduct: https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.ovirt.... List Archives: https://eur02.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.ovir... To view the terms under which this email is distributed, please go to:- http://leedsbeckett.ac.uk/disclaimer/email/

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