Re: [Xen-devel] PATCH: Fix name uniqueness check

[Masaki Kanno <kanno.masaki@xxxxxxxxxxxxxx>]

Hi,

I tested xen-unstable 15967 and staging 15973.

[xm create]
 if an UUID is specified:
     if a VM with same name exists:
         if the VM is same UUID too:
             ==> xm create succeed, but...
             # xm list
             Name     ID   Mem VCPUs      State   Time(s)
             Domain-0  0   491     2     r-----    109.3
             vm1       2   256     1     r-----   3636.3
             vm1       4   256     1     --p---      0.0
             
         else:
             ==> xm create failed
             Error: VM name 'vm1' already exists as domain 2
             
     else:
         if a VM with same UUID exists:
             ==> xm create succeed... Right?
             
         else:
             ==> xm create succeed
             
 else:
     if a VM with same name exists:
         ==> xm create failed
         Error: VM name 'vm1' already exists as domain 2
         
     else:
         ==> xm create succeed
         

[xm new]
 if an UUID is specified:
     if a VM with same name exists:
         if the VM is same UUID too:
             ==> xm new failed?  but an error message was not shown.
             # xm new /xen/vm2.conf name="vm1"
             Using config file "/xen/vm2.conf".
             # xm list
             Name     ID   Mem VCPUs      State   Time(s)
             Domain-0  0   491     2     r-----    243.9
             vm1       2   256     1     r-----  10003.1
             
         else:
             ==> xm new failed
             Error: Domain name 'vm1' is already used.
             
     else:
         if a VM with same UUID exists:
             ==> xm new failed
             Error: Domain UUID '3ef95bbe-57a9-1caf-9a15-27ab27eb66b3' 
                    is already used.
         else:
             ==> xm new succeed
             
 else:
     if a VM with same name exists:
         ==> xm new failed?  but an error message was not shown.
         
     else:
         ==> xm new succeed
         

Best regards,
 Kan

Thu, 27 Sep 2007 17:50:51 +0100, "Daniel P. Berrange" wrote:

>Changeset  15124:f5459c358575 altered check_name() in XendDomainInfo so that
>it compares domain IDs instead of UUIDs. This breaks a number of things
>
> - You can no longer use 'xm new' to define a persistent config file for
>   a running guest. This breaks the key OS provisioning scenario where
>   you boot a kenrel+initrd for the installer, and at the same time define
>   a permanent config with pygrub.
>
> - It lets you define multiple inactive guests with different UUIDs, but  
>   the same name because all inactive guests have a domid of None. So you
>   can now end up with multiple guests with same name, which is contrary
>   to the goal implied by the patch which was name uniqueness.
>
>It is unclear from the original commit logs just what scenario it was trying
>to protect against, but the original checking of uniqueness based on UUID 
>was correct & is what was used in previous releases XenD.
>
>Thus the attached patch reverts 15124
>
>   Signed-off-by: Daniel P. Berrange <berrange@xxxxxxxxxx>
>
>Regards,
>Dan.
>-- 
>|=- Red Hat, Engineering, Emerging Technologies, Boston.  +1 978 392 2496 -=|
>|=-           Perl modules: http://search.cpan.org/~danberr/              -=|
>|=-               Projects: http://freshmeat.net/~danielpb/               -=|
>|=-  GnuPG: 7D3B9505   F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505  -
>|=| 
>
>-------------------------------text/plain-------------------------------
>_______________________________________________
>Xen-devel mailing list
>Xen-devel@xxxxxxxxxxxxxxxxxxx
>http://lists.xensource.com/xen-devel

----
菅野 大樹/Masaki Kanno,TEL 055-924-7349(7551-5366),富士通(株)沼津工場B4F
サーバ本)Linux技術開発統括部 kanno.masaki@xxxxxxxxxxxxxx


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel