XenD lost its uniqueness check for names & UUIDs

XenD lost its uniqueness check for names & UUIDs

[Daniel P. Berrange]

I'm doing some testing against today's xen-unstable.hg and it appears that
XenD has lost its uniqueness checks for names & UUIDs. eg

# xm create XenGuest2
Using config file "/etc/xen/XenGuest2".
Started domain XenGuest2
# xm create XenGuest2
Using config file "/etc/xen/XenGuest2".
Started domain XenGuest2
# xm create XenGuest2
Using config file "/etc/xen/XenGuest2".
Started domain XenGuest2
# xm list
Name                                      ID   Mem VCPUs      State   Time(s)
Domain-0                                   0   698     2     r-----   2915.3
XenGuest1                                 24   394     4     -b----     32.0
XenGuest2                                 32   300     1     r-----      0.3
XenGuest2                                 30   300     1     ------      3.2
XenGuest2                                 31   300     1     --p---      0.0

# xm list --long | grep uuid | sort | uniq -c
      1     (uuid 00000000-0000-0000-0000-000000000000)
      1     (uuid c7a5fdb0-cdaf-9455-926a-d65c16db1809)
      3     (uuid c7a5fdb2-cdaf-9455-926a-d65c16db1809)

So I now have 3 active guests with same name and same UUID :-(

Now it should always be possible to run 'xm new' to define a persistent 
config file for a transient domain, but, attempts to run 'xm create' 
should be rejected if there is an existing domain.

Dan.
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Re: XenD lost its uniqueness check for names & UUIDs

[Daniel P. Berrange]

On Thu, Apr 12, 2007 at 01:51:17AM +0100, Daniel P. Berrange wrote:
> I'm doing some testing against today's xen-unstable.hg and it appears that
> XenD has lost its uniqueness checks for names & UUIDs. eg
> 
> # xm create XenGuest2
> Using config file "/etc/xen/XenGuest2".
> Started domain XenGuest2
> # xm create XenGuest2
> Using config file "/etc/xen/XenGuest2".
> Started domain XenGuest2
> # xm create XenGuest2
> Using config file "/etc/xen/XenGuest2".
> Started domain XenGuest2
> # xm list
> Name                                      ID   Mem VCPUs      State   Time(s)
> Domain-0                                   0   698     2     r-----   2915.3
> XenGuest1                                 24   394     4     -b----     32.0
> XenGuest2                                 32   300     1     r-----      0.3
> XenGuest2                                 30   300     1     ------      3.2
> XenGuest2                                 31   300     1     --p---      0.0
> 
> # xm list --long | grep uuid | sort | uniq -c
>       1     (uuid 00000000-0000-0000-0000-000000000000)
>       1     (uuid c7a5fdb0-cdaf-9455-926a-d65c16db1809)
>       3     (uuid c7a5fdb2-cdaf-9455-926a-d65c16db1809)
> 
> So I now have 3 active guests with same name and same UUID :-(
> 
> Now it should always be possible to run 'xm new' to define a persistent 
> config file for a transient domain, but, attempts to run 'xm create' 
> should be rejected if there is an existing domain.

This is slightly more interesting than I first thought - there is a name
uniqueness check being performed, but it only appears to be done if the
UUID's are different. ie, if I have 2 config files with same name, but
different UUIDs, XenD correctly refuses to start the 2nd. If I have 2
config files with same name & same UUID, it happily starts both.

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  -=|