[ILUG] Libvirtd & kvm: mount directory from host in guest

[David De La Harpe Golden]

On 18/11/10 14:44, Bailey, Darragh wrote:
>
>
> Is there an equivalent feature in libvirtd&  kvm to make directories on
 > the host system available in the guests? I recall this being available
 > in VMWare but not 100%.
>

IIRC VMWare autoconfigures a (possibly modified) samba for you 
underneath, at least on a linux physical host.  I dunno what it does on 
a windows physical host, but probably just uses windows' native cifs 
support.

n.b. qemu/kvm  support autoconfiguring samba to provide shares for 
guests from the host, as simple as e.g.
"-net user,smb=/srv/smbtmp" on the command line

...though whether the libvirt wrapper has any automatic management of 
that in particular I don't know off the top of my head.

> If not, I'll have to decide between sharing a disk image between guests

Uhm. If I'm not misunderstanding, that's unlikely to work well _at all_ 
at all unless you were to run a true shared-block-device clustered fs 
across the guests, like GFS. And you probably don't to want to get into 
that, though it might be academically interesting, it would be a pretty 
odd setup for most purposes.

> or using NFS to provide some local scratch space so users of the
 > different guests can easily access the same local data no matter
 > which one they are actually on.

Well, that's very similar to using samba, only, well, nfs.  So perhaps 
better fit for linux/unixy guests, worse fit for windozey guests.

(just in case: don't confuse that with the libvirt "nfs storage pool" - 
AFAIK that means using an nfs server to store the disk images for a 
bunch of guests).