[Linux-cluster] Can i use 2 nodes from a cluster?

[Marcelo Roccasalva]

On Tue, Oct 22, 2013 at 9:41 AM, fosiul alam <expertalert at gmail.com> wrote:
> Hi
>
> I am trying to build a redhat cluster with 4 nodes for High Availability and
> load balancing.
>
> example :
>
> node1,node2,node3,node4 for apache service + Centralized Storage.
>
> now when those 4 nodes are connecting into cluster, i can only use 1 node at
> a time and when 1 node goes down then it shift all services into node2 .
>
> but can i not use all 4 nodes a  time ??
>
> example, i have a hardware load balancer, From this  can i not pass the http
> trafiq to all 4 nodes ??
>
> if not then how can i have load balanced between these 4 nodes ??

You need a failoverdomain nofailback restricted for every node, and a
service for apache on every node, Untested relevant part of
cluster.conf:

 <rm>
                <resources>
                        <script file="/etc/init.d/httpd" name="httpd"/>
                </resources>
                <failoverdomains>
                        <failoverdomain name="only_node1"
nofailback="1" restricted="1">
                                <failoverdomainnode name="node1"/>
                        </failoverdomain>
                        <failoverdomain name="only_node2"
nofailback="1" restricted="1">
                                <failoverdomainnode name="node2"/>
                        </failoverdomain>
...
                </failoverdomains>
                <service domain="only_node1" name="apache1" recovery="restart">
                        <script ref="httpd"/>
                </service>
                <service domain="only_node2" name="apache2" recovery="restart">
                        <script ref="httpd"/>
                </service>
...
</rm>

Anyway, if you need the same services running in every node, you don't
need a cluster ;-)

Regards,

--
Marcelo

¿No será acaso que esta vida moderna está teniendo más de moderna que de
vida?" (Mafalda)