On Wed, Apr 06, 2016 at 10:28:44AM +0200, Dmitry Tantsur wrote: > Hi OOO'ers! > > I'd like to get your permission to backport > https://review.openstack.org/#/c/288417/ to stable/{liberty,mitaka} or seek > alternative suggestions on how to make life easier for folks upgrading for > Kilo. > > The context of the problem is the following. In the Liberty release we (with > the whole Ironic world) have switched from the old bash-based Ironic deploy > ramdisk to IPA. I can't talk enough about benefits that it brought us, but > today I want to talk about one drawback. > > IPA has a different logic for choosing the root device for deployment, when > several root devices are present. The old ramdisk always tried to find a > disk by name present in the Ironic disk_devices configuration option, > defaulting to something like "sda,hda,vda". IPA takes the smallest device > which is greater than 4 GiB. Obviously, it's not guaranteed to be the same. > > What it means is that when people upgrade their undercloud from Kilo and > Liberty and beyond, and rebuild an overcloud node, this node may end up with > a different root device picked by default. In the absence of cleaning, that > will probably result in deployment failure (e.g. due to duplicated config > drive). > > A side note: the same was possible and actually happened back in Kilo, > because device names are not reliable, and can change between reboots. > > Now, the Ironic team has always recommended using root device hints for > several root devices. However, there are valid complaints from users that > running node-update on every node is not really convenient. And he is the > patch in question: it adds a new flag to 'baremetal configure boot' to > bulk-set root device hints based on a strategy or list of device names. The > root device information is fetched from the introspection data. This allows > people upgrading from Kilo to just do: > > openstack baremetal configure boot --root-device=sda,hda,vda > > to create root device hints matching the previous behavior. I suggest we > backport this patch to simplify life for people.
+1 - I think we can consider this a bug, e.g from a user perspective choosing the wrong/different device after upgrade is a bug, and this provides a way around it. So I'd suggest you raise a bug (if one doesn't already exist) and propose the backports. Also it would appear from a quick look at the patch that it's low-risk from a backport perspective, as it adds new options which a user may ignore if they desire the default (current) behavior instead. Thanks! Steve __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: [email protected]?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
