[Linux-cluster] RH5 and clustering

[Robert Peterson]

Tarun Reddy wrote:
> Simple question, possibly complicated answer:
>
> Will RH5's cluster change dramatically from RH4s? (see RH3 to RH4 
> cluster changes for example of drastic :-)
>
>
> Thank you,
>
> Tarun 
Hi Tarun,

There are a number of changes in the cluster code between RHEL4 and 
RHEL5, many of which are internal
and should be transparent to users.  I'll outline a few of the changes:

Most noticeable user changes:

1. Cool new web-based cluster administration tool called Conga.
2. Cluster.conf has a new "nodeid=X" requirement.
3. GFS2 now available as a tech preview, with fs, userland tools such as 
mkfs.gfs2, gfs2_fsck, gfs2_convert, etc.
4. Centralized init script: service cman start  (not counting clvmd and 
gfs init scripts.)
5. No more lock_gulm locking protocol.  Users encouraged to use dlm locking.

Some of the less noticed internal changes:

1. A lot of code has been moved from the kernel to userland for better 
system integrity and easier debugging.
2. New group daemons: groupd, gfs_controld, dlm_controld.
3. Cluster infrastructure built on top of openais cluster technology.
4. DLM and GFS2 now part of the base kernel (accepted upstream).
5. Lots of little improvements.

There are more, but I'm drawing a blank at the moment.

Regards,

Bob Peterson
Red Hat Cluster Suite