[PKG-Openstack-devel] Bug#774788: Bug#774788: Bug#774788: neutron-metadata-agent overwrites config on update

[Thomas Goirand]

On 01/10/2015 11:22 AM, Benedikt Trefzer wrote:
> Hi Thomas
> 
>>> I currently not able to imagine where it reads the config file. (Sorry
>>> ;(). Especially I cannot understand why it does eg not change the region
>>> which seems to me like equivalent configured.
>>
>> The values are read from within the pkgos_read_admin_creds function of
>> openstack-pkg-tools. The function is called this way in the
>> debian/neutron-metadata-agent.config.in:
>>
>> pkgos_read_admin_creds ${META_AGNT_CONF} DEFAULT neutron-metadata
>>
> 
> Ok I found this one. the function pkgos_read_admin_creds() in postinst
> script is never run. instead the one in config is used.
> (Probably we should delete the
> pkgos_read_admin_creds() definition in postinst, since it is never used
> there.)

What is done is that *all* of the openstack-pkg-tools functions are
added to both the config and postinst script. Probably the file could be
split in 2 different libs, but that's not the way it is done currently.
I don't think it's a big issue though.

Yes, pkgos_read_admin_creds() is used only in the config script, as it
should be...

> Anyway. I understood the function itself.
> 
> And I found the bug !
> 
> The function looks for the config parameter
> auth_host, which is not defined in metadata_agent.ini (it is in
> neutron.conf)
> It then overwrites the auth_url parameter.
fa>
> But actually it should look first at auth_url, extract auth_host from
> there and then write auth_url again.
> 
> If I define auth_host in metadata_agent.ini file, you're script seems to
> work (this is a workaround for the problem).
> But according to openstack code auth_host is not a defined configuration
> option in metadata_agent.ini file.
> 
> I can imagine the following solutions:
> - rewrite pkgos_read_admin_creds() to use auth_url values (and this
>   without braking other invocations of this function !)
> 
> - define pkgos_read_admin_creds_metadata_only() function as a
>   replacement in metadata-agent.
> 
> - introduce debconf neutron-metadata/auth_url and remove
>   neutron-metadata/auth_host and change the scripts accordingly.
> 
> I'm currently not capable of implementing any of these three solutions.
> Any other ideas ?

I think it should be fine to re-implement pkgos_read_admin_creds and
pkgos_write_admin_creds specifically for the metadata server .ini file.
I'll work on this tomorrow.

Cheers,

Thomas Goirand (zigo)