[Engine-devel] [vdsm] ovirt-host-deploy and multible bridges

[Sahina Bose]

On 04/10/2013 12:25 AM, Dan Kenigsberg wrote:
> On Tue, Apr 09, 2013 at 07:28:17PM +0530, Balamurugan Arumugam wrote:
>> On 04/09/2013 06:37 PM, Sahina Bose wrote:
>>> Decoding "correct address"  - glusterHostsList should return any
>>> ipAddress that engine knows as being associated with host.
>>> It could be either ipAddress used while adding host (stored as hostname
>>> in vds_static) or any of the ipAddresses populated in vds_interface
>>> table (addr column) .
>>> I do not have enough knowledge about this bit of code to say what
>>> entries are made in vds_interface table. I know there's an entry for
>>> ovirtmgmt here but not sure if this gets added as part of addHost flow
>>> or not.
>>>
>> I guess, vds_interface table is populated by ips given by vdsm
>> through getVdsCaps.
>>
>> Current glusterHostsList provides one of ipaddress of the local host
>> (other than 127.*.*.*).   If virbr0 is enabled, it picks up
>> 192.168.122.1 ip address of the bridge and sends to the engine, but
>> this entry is missing in the table.
>>
>> The requirement is that we need a ip of the local host which is also
>> stored in the database.
>>
>> The database has entries of ips of a host those are from physical
>> nics and/or bridges who has slaves to nics.
> It's not something I've tested, or want to encourage, but currently,
> outside of gluster, Vdsm may run behind a fancy NAT as a virtual server.
> I.e., its local undress may be utterly different from the address used
> by Engine.
>
> I'd like to keep having this flexibility, and not to assume otherwise.
>
> Why does glusterHostsList need to return the ip of the management
> network? The client that issued this verb has to know that IP in the
> first place.
>
> I notice that the idiom "_getLocalIpAddress() or _getGlusterHostName()"
> is used all too often in vdsm/gluster/cli.py.
>
> How about changing the Vdsm/Engine API so that the string "localhost" is
> returned instead? Then, Engine can replace it with whatever it seems
> fit.
>
> Dan.
Dan,

Thanks for clarifying. Looks like relying on the IpAddress to determine 
the host will be prone to errors going forward.
We will change the approach and start using the UUID that gluster peer 
status returns to identify host - will create a new verb glusterPeerList 
that does this.

And for the current host, like you mentioned, since the engine already 
knows which vdsm host this command is executed on, the engine will not 
rely on vdsm to return the host's IP.

thanks
sahina