well, this does not reproduce to me (nor current U/S, 3.4, or the build you mentioned). 

From what browser is that stack trace? (because they are different for each). 

Could you please attach the stack from the firefox?

Also please attach the relevant engine logs.

Thank you

(In reply to Tomas Jelinek from comment #2)
> well, this does not reproduce to me (nor current U/S, 3.4, or the build you
> mentioned). 
> 
> From what browser is that stack trace? (because they are different for
> each). 
> 
> Could you please attach the stack from the firefox?
> 
> Also please attach the relevant engine logs.
> 
> Thank you

Hi,

It was google-chrome. I have reproduced the issue with firefox 27.0.1. I would like to point out that the DC taht I use to reproduce is Local type.


POST https://rhevm33/webadmin/webadmin/GenericApiGWTService [HTTP/1.1 200 OK 7ms]
13:31:22.808 "Mon Mar 03 13:31:22 GMT+100 2014 com.google.gwt.logging.client.LogConfiguration
SEVERE: (TypeError) 
 stack: qSj@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:16320
swl@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:16477
Jij@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:15341
Mij@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:16447
qqd@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:16390
LM@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:13943
cN@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:16390
T9d/c.onreadystatechange<@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:11410
Uq@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:7954
Xq@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:14543
Wq/<@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:12067

 fileName: https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html
 lineNumber: 16320
 columnNumber: 1305: e is null
com.google.gwt.core.client.JavaScriptException: (TypeError) 
 stack: qSj@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:16320
swl@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:16477
Jij@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:15341
Mij@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:16447
qqd@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:16390
LM@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:13943
cN@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:16390
T9d/c.onreadystatechange<@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:11410
Uq@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:7954
Xq@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:14543
Wq/<@https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html:12067

 fileName: https://rhevm33/webadmin/webadmin/703514569DB8B555E64E057CF39EEA11.cache.html
 lineNumber: 16320
 columnNumber: 1305: e is null
	at Unknown.qSj(Unknown Source)
	at Unknown.swl(Unknown Source)
	at Unknown.Jij(Unknown Source)
	at Unknown.Mij(Unknown Source)
	at Unknown.qqd(Unknown Source)
	at Unknown.LM(Unknown Source)
	at Unknown.cN(Unknown Source)
	at Unknown.T9d/c.onreadystatechange<(Unknown Source)
	at Unknown.Uq(Unknown Source)
	at Unknown.Xq(Unknown Source)
	at Unknown.Wq/<(Unknown Source)
	at Unknown.anonymous(Unknown Source)" 703514569DB8B555E64E057CF39EEA11.cache.html:16390
13:31:24.129 POST https://rhevm33/webadmin/webadmin/GenericApiGWTService [HTTP/1.1 200 OK 46ms]

Thank you for the new logs - now I see the issue. The problem is with the incorrect selection of the default host when changing from one DC with some hosts to a different one with some hosts.

Until the fix will be available you can use a simple workaround:
after selecting the local DC go to  "Host side tab" -> "Start Running On" -> "Specific" and select some host.

Than you should be able to create a VM.

Roman, does the workaround mentioned above work?

(In reply to Tomas Jelinek from comment #7)
> Roman, does the workaround mentioned above work?

Hi,

thank you for pointing that out. I used REST API to create the VM.

I just wanted to make sure that it will be fixed.

Thanks
Roman

Verified in ovirt-engine-3.5.0-0.0.master.20140804172041.git23b558e.el6.noarch (rc1).

Verification steps:
1. Have the Default data center stuffed with Default cluster, host and active storage.
2. Add second - local - data center LocalDC plus cluster LocalCL, host and local storage.
3. VMs tab -> New VM -> switch Default cluster to LocalCL.
   Enter VM name and submit.

Result:
New VM in LocalDC is created, no errors occured in engine.log or browser console.

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHSA-2015-0158.html