I'm all for adding a bit of additional smarts to cloudstack so it can workaround the current KVM limitations. Waiting for anything to get fixed up stream is affecting deployments NOW, and a bit utopian. cloudstack seems to be the lower barrier to entry on getting these scenarios addressed.
On Wed, Mar 19, 2014 at 1:29 PM, Edison Su <edison...@citrix.com> wrote: > It's hard to find root cause and fix something in libvirt, even we found > the root cause, it's hard to push the fix into libvirt upstream, and not to > say push into downstream, like RHEL 6 etc. For example, we already have a > fix for the bug https://bugzilla.redhat.com/show_bug.cgi?id=977706 for a > few month now, there is no resolution to resolve the issue. Without the > fix, we just simply are blocked to support newer version of KVM. > > So if community doesn't like what I proposed, then how about another way: > I will write a new implementation of KVMStoragePool interface, which will > be backed by java/python/shell script, it won't be enabled by default. > It's a simple thing, don't understand why libvirt gets it done so > complicated, and introduce a lot of pain. > > > -----Original Message----- > > From: Nux! [mailto:n...@li.nux.ro] > > Sent: Wednesday, March 19, 2014 12:35 PM > > To: dev@cloudstack.apache.org > > Subject: Re: [RFC]Bypass Libvirt storage pool for NFS > > > > On 19.03.2014 19:01, Wido den Hollander wrote: > > > On 03/19/2014 07:54 PM, Edison Su wrote: > > >> I found many times in QA's testing environment, the libvirt storage > > >> pool(created on NFS) is missing on the kvm host frequently, for no > > >> reason. It may relate to bug > > >> https://bugzilla.redhat.com/show_bug.cgi?id=977706. > > >> In order to fix this issue, and bug CLOUDSTACK-2729, we added a lot > > >> of workaround to fight with libvirt, such as, if can't find the > > >> storage pool, then create the same pool again etc. As the storage > > >> pool can be lost on kvm host at any time, it will cause a lot of > > >> operation errors, such as can't start vm, can't delete volume etc, > etc. > > >> I want to bypass libvirt storage pool for NFS, as java itself, > > >> already have all the capabilities that libvirt can provide, such as > > >> create a file, delete a file, list a directory etc, there is no need > > >> to add another layer of crap here. In doing so, we won't be blocked > > >> by libvirt bug(https://bugzilla.redhat.com/show_bug.cgi?id=977706) to > > >> support newer version of KVM. > > >> > > > > > > -1 > > > > > > I understand the issues which we see here, but imho the way forward is > > > to fix this in libvirt instead of simply go around it. > > > > > > We should not try to re-invent the wheel here, but fix the root-cause. > > > > > > Yes, Java can do a lot, but I think libvirt can do this better. > > > > > > For the RBD code I also had a couple of changes go into libvirt > > > recently and this NFS issue can also be fixed. > > > > > > Loosing NFS pools in libvirt is most of the times due to a restart of > > > libvirt, they don't magically disappear from libvirt. > > > > > > I agree that we should be able to start the pool again even while it's > > > mounted, but that's something we should fix in libvirt. > > > > > > Wido > > > > -1 and 100% with Wido. If libvirt gets fixed then it would save loads of > code in > > the future and bring other benefits (think support for Xen Project via > libvirt > > etc). > > Let's push for libvirt fix instead. > > > > My 2 cents, > > Lucian > > > > > > -- > > Sent from the Delta quadrant using Borg technology! > > > > Nux! > > www.nux.ro >
