Re: [libvirt] [PATCH v2 1/2] Qemu/Gluster: Add Gluster protocol as supported network disk formats.

On Fri, Oct 26, 2012 at 15:06:19 +0530, Harsh Bora wrote: > On 10/05/2012 05:27 PM, Paolo Bonzini wrote: >> Il 04/10/2012 15:31, Harsh Prateek Bora ha scritto: >>> Qemu accepts gluster protocol as supported storage backend beside others. >>> This patch allows users to specify disks on gluster backends like this: >>> >>> <disk type='network' device='disk'> >>> <driver name='qemu' type='raw'/> >>> <source protocol='gluster' name='volume/image'> >>> <host name='example.org' port='6000' transport='tcp'/> >>> </source> >>> <target dev='vda' bus='virtio'/> >>> </disk> >>> >>> Note: In the <host> element above, transport is an optional attribute. >>> Valid transport values are tcp, unix or rdma. If none specified, tcp is assumed. >>> If transport type is unix, host name specifies path to unix socket. >> >> I would rather add a new attribute "socket" than overload the host name. >> The host name for Unix sockets is really localhost. > > After looking into the URI infra, I realized, it is better to have the > new attribute name as 'query' since socket=</path/to/socket> in > qemu-gluster commandline is nothing but a query in the whole URI > following by a '?' character. > > Since, the _virURI struct in libvirt also has a member 'query' for the > query string in a URI, it makes sense to keep the XML attribute as > generic as that so that it can be used by others for related purpose. > > Needless to say, users will have to specify sockets as > <host name='example.org' port='6000' transport='unix' > query='socket=/path/to/sock' /> Ah, this looks horrible. We really want to avoid specifying random garbage for hostname and port in case of unix transport. What Paolo is suggesting is to create <host name='example.org' port='6000' transport='tcp'/> or <host socket='/path/to/sock' transport='unix'/> However, I don't like this too much either. What if we add a general socket element? In other words, <host name='example.org' port='6000' transport='tcp|rdma'/> or <socket type='unix' path='/path/to/sock'/> where the type attribute in socket element would determine what other attributes can be used (path for unix sockets). Internally, both elements could be described by a unified socket structure.

Jirka