On 2015-05-21 3:38 PM, Chris Friesen wrote: > On 05/21/2015 03:20 PM, Mathieu Gagné wrote: >> On 2015-05-21 3:13 AM, Daniel P. Berrange wrote: >>> On Thu, May 21, 2015 at 09:34:20PM +1200, Xav Paice wrote: >>>> On 21/05/15 21:23, Daniel P. Berrange wrote: >>>>> On Wed, May 20, 2015 at 03:01:50PM -0700, Michael Still wrote: >>>>>> I note that we use instance.name to lookup the libvirt domain a bunch >>>>>> in the driver. I'm wondering why we don't just use instance.uuid all >>>>>> the time -- the code for that already exists. Is there a good reason >>>>>> to not move to always using the uuid? >>>>>> >>>>>> I ask because instance.name is not guaranteed to be unique depending >>>>>> on how weird the nova deployment is. >>>>> Agreed, there's no benefit to using name - internally libvirt will >>>>> always >>>>> prefer to use the UUID itself too. >>>>> >>>>> These days though, there is only a single place in nova libvirt driver >>>>> that needs updating - the nova.virt.libvirt.host.Host class >>>>> get_domain() >>>>> method just needs to be switched to use uuid. >>>> >>>> Just a comment from an ops point of view - it would be miles easier >>>> when >>>> trying to troubleshoot, if the instance name was the uuid anyway. I >>>> totally agree on using instance.uuid, just to comment that I find it a >>>> little painful sometimes that instance names don't match the uuid of >>>> the >>>> instance, but the directory structure does. Just a bit of confusion to >>>> avoid at 2am when something isn't working. >>> >>> You do know you can configure the instance name used... >>> >>> eg in nova.conf >>> >>> instance_name_template='inst-%(uuid)s' >>> >> >> Please note that you CANNOT change instance_name_template ones instances >> are created otherwise they become unmanageable by Nova. This is because >> Nova tries to find the libvirt instance by its name instead of its UUID. >> So since instances were spawned with the old value, it won't find >> existing instances using the new value. >> >> And no, I haven't found a way to rename an instance without >> redefining/restarting it in libvirt. > > Is there any reason why we couldn't default to using something like > 'inst-%(uuid)s' for the instance name? >
I guess it's for the reason I mentioned above: To not break all OpenStack installations on Earth running with default config values. -- Mathieu __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev