CTDB in Samba4

[Abhijith Das]

tridge at samba.org wrote:

>The one area where filesystem specific code is likely to be needed is
>some way of asking the filesystem what cluster nodes are
>present. Ideally we would also have a notifcation mechanism when new
>nodes are added. So far we have no hooks for this (we're just using a
>flat text file for the list of nodes), but that will change.
>
Hi Tridge,
The GFS is not aware of the cluster membership.
Red Hat's cluster suite uses cman (based on openais: 
http://developer.osdl.org/dev/openais/) to handle cluster memberships. 
(http://people.redhat.com/pcaulfie/docs/aiscman.pdf)
Among other things, it exposes an API for cluster membership to external 
applications.
API exposed by libcman:
http://sources.redhat.com/cgi-bin/cvsweb.cgi/cluster/cman/lib/libcman.h?rev=1.29&content-type=text/x-cvsweb-markup&cvsroot=cluster&only_with_tag=HEAD
Simple example of using libcman:
http://sources.redhat.com/cgi-bin/cvsweb.cgi/cluster/cman/tests/libtest.c?rev=1.6&content-type=text/x-cvsweb-markup&cvsroot=cluster&only_with_tag=HEAD

--Abhi