[ovirt-users] Terribly slow web consile post migration of oVirt Engine from one host to another host

[Alexander Wels]

On Thursday, June 09, 2016 12:28:41 PM Anantha Raghava wrote:
> Hello Alexander,
> 
> You are right. The FQDN was the culprit. Once I entered the FQDN in
> /etc/hosts file, the problem got resolved.
> 
> Thanks for your guidance.
> 
> By the way any document that explains what is --restore-permissions in
> engine-backup process?
> 

If you type engine-backup --help you will get a list and explanation of all 
the possible options. 

Affects only the custom dump format. Will not pass to pg_restore '--no-owner --
no-privileges'. Might not work as expected with the --*db-user options.

Is what the --help says, not sure what that means though.

> > Hi,
> > 
> > I will try both options tomorrow & revert back here.
> > 
> > Regards,
> > Anantha Raghava
> > 
> > On Jun 8, 2016 10:04 PM, "Alexander Wels" <awels at redhat.com
> > 
> > <mailto:awels at redhat.com>> wrote:
> >     On Wednesday, June 08, 2016 08:49:16 PM Anantha Raghava wrote:
> >     > Hi,
> >     > 
> >     > I was able to migrate the oVirt Engine from one host to another
> >     
> >     using
> >     
> >     > engine-backup utility. On the new host, the data is loaded
> >     
> >     properly but
> >     
> >     > the Administration Portal is terribly slow.
> >     > 
> >     > It take about 2 to 3 minutes to allow me to enter user name &
> >     
> >     password.
> >     
> >     > Once logged in, it takes hell a lot of time to show up the data.
> >     
> >     Click
> >     
> >     > on a tab, we need to wait for a good amount of time to see the
> >     
> >     actual
> >     
> >     > data. Even the refresh is taking time to execute although it is
> >     
> >     set to 5
> >     
> >     > Seconds.
> >     > 
> >     > But if I enable old server and connect, every thing works quickly.
> >     > 
> >     > Note:
> >     > 
> >     > 1. We do not have DNS in our environment.
> >     > 2. Engine name & even the IP is retained the same.
> >     > 3. Before migration, we stopped ovirt-engine on old server, took the
> >     > backup, shutdown & disconnected the old server.
> >     > 4. We installed the ovirt-engine on new server, run engine
> >     
> >     setup, noted
> >     
> >     > down the DB password, did engine-cleanup, restored the data using
> >     > engine-backup utility and executed engine-setup again. It did
> >     
> >     recognize
> >     
> >     > restored data and only httpd configuration was sought and we
> >     
> >     selected
> >     
> >     > the defaults.
> >     
> >     It is highly likely 1 of 2 things:
> >     
> >     1. The entropy mentioned by Brett, however that is mostly
> >     applicable on hosted
> >     engine as VMs don't usually have good entropy.
> >     2. The engine cannot resolve itself (which looking at your
> >     description is the
> >     likely culprit). Since you don't have DNS, you need to add the fqdn to
> >     /etc/hosts so it can resolve itself.
> >     
> >     > Result is terribly slow Web Console.
> >     > 
> >     > First, we attempted to setup ovirt-reports and later removed it
> >     
> >     thinking
> >     
> >     > that may be slowing down the engine server. Yet the same result.
> >     > 
> >     > Commands used to backup from old server: "engine-backup
> >     
> >     --mode=backup
> >     
> >     > --file=<filename> --log=<log file name> --provision-db"
> >     > Command used to restore on new server: "engine-backup --mode=restore
> >     > --file=<backup-file-name> --log=<log-file-name>
> >     
> >     --change-db-credentials
> >     
> >     > --db-host=localhost --db-user=engine --db-name=engine
> >     > --db-password=<password noted down in step 4>
> >     
> >     --no-restore-permissions"
> >     
> >     > The command executed without any errors, resulting in a terribly
> >     
> >     slow
> >     
> >     > web console.
> >     > 
> >     > Note: Without --restore-permissions, the restore fails. Did not
> >     > understand what to give as restore permissions. Hence used
> >     > --no-restore-permissions.
> >     > 
> >     > *Hardware configuration:*
> >     > *
> >     > **Old Server:* i3 Processor, 4 GB Memory, 1 Gbps NIC
> >     > *New Server :* Lenovo x3250 M5 Server with Intel Xeon Processor,
> >     
> >     16 GB
> >     
> >     > RAM, 2 X 1 Gbps NIC.
> >     > 
> >     > Just unable to understand why it is terribly slow.