Edison, Enabling/disabling local storage at host level is a good option for a small deployment where the number of host is < 20-30. For a large deployment configuring this for each host is not a very clean experience from the admin perspective. Hence the idea of doing it at some grouping level (cluster/pod/zone).
Nitin, When local storage is enabled (say at cluster level), then on any new host addition the local storage for it also gets added. For existing hosts local storage shows up on MS restart. Also if disabled already created storage pools will still remain, only new storage pools won't get added. -Koushik -----Original Message----- From: Edison Su [mailto:edison...@citrix.com] Sent: Friday, August 03, 2012 1:35 AM To: cloudstack-dev@incubator.apache.org Subject: RE: Local storage support for data volumes > -----Original Message----- > From: Nitin Mehta [mailto:nitin.me...@citrix.com] > Sent: Thursday, August 02, 2012 8:18 AM > To: cloudstack-dev@incubator.apache.org > Subject: RE: Local storage support for data volumes > > David - I think the cluster is supposed to be homogeneous in terms of > hardware and hypervisor version and selectively having local storage > for hosts shouldn't be a problem. Allocation also looks at cluster to > have a rough idea if the vm can be accommodated or not. > Since the local storage is tied at the host level I wanted to find > community's viewpoint if we want the flexibility at the lowest level > or not. Local storage is per host, not per cluster, and it's not created by cloudstack mgt server. If admin doesn't want local storage for a particular host, he can disable it during hypervisor host installation or setup. What's the usage case to put the local storage at zone/cluster level? > > But then on second thought I myself don't see a lot of merit of having > this flexibility at the host level at the moment and it might become > little tedious for the admin to disable local storage. > Another concern is that if you have the flag at cluster/zone level > then how would you enable it on the fly - would you be creating local > storages for all the hosts within that cluster/zone ? Has that been > addressed ? > > Thanks, > -Nitin > > -----Original Message----- > From: David Nalley [mailto:da...@gnsa.us] > Sent: Thursday, August 02, 2012 5:22 PM > To: cloudstack-dev@incubator.apache.org > Subject: Re: Local storage support for data volumes > > On Tue, Jul 31, 2012 at 5:34 AM, Nitin Mehta <nitin.me...@citrix.com> > wrote: > > Can we not provide the flexibility while adding a host. So when the > admin adds a host he has the provision of enabling/disabling local > storage for that host. I think that is the lowest level of granularity > that we can provide to the admin ? > > But hosts within a cluster are supposed to be homogenous. And aren't > allocation planning decisions made at the cluster level? What benefit > do you see by making this specific to the host as opposed to the > cluster? > > --David