How to create a virtual IP/hostname for a 2 nodes cluster

[crypto grid]

On Wed, Aug 12, 2009 at 10:14 AM, Herta Van den Eynde <
herta.vandeneynde at gmail.com> wrote:

> As this is only a two node cluster, why would you add a load balancer?


AFAIK, LVS is, indeed a load balancer. There is no way you can run an a-a
service in the cluster without a balanced ip.


>
>
> LVS will give you a unique ip-address per service that you are running in
> the cluster.  I.e. in your case, you'll get 2 fixed ip-addresses (one for
> each server) and three virtual addresses (one for each service).
> When one of the servers goes down, the services (including the virtual
> addresses) running on that server will automatically migrate to the other
> server.


I saw some customers who didn't want to install red hat lvs in their
clusters. Instead, they insisted to use external loadbalancers, and
personally, I have no objection with that, because in some way, you are
taking some "complexity" out of the servers.
Sorry for going off at a tangent.


>
>
> There are a number of caveats, though.
> 1. you need central storage and a cluster-aware filesystem
> 2. when services fail over to the other node (either because of server
> failure or manually), the services are stopped (or crash) on the first
> server and are restarted on the second.  I.e. running processes do not
> continue running.  I.e. your applications (and end-users) have to know that
> when your database fails over, they will have to reconnect.
>
> I have no experience with Oracle iAS, or E-business Suite 11i, but if you
> want to cluster Oracle databases, Oracle RAC (Real Application Cluster) is
> the way to go.
> Undoubtedly, Oracle can at least let you know the best way to add
> redundancy for Oracle iAS and E-business Suite 11i.
>
> Kind regards,
>
> Herta
>
>
> 2009/8/10 crypto grid <cryptogrid at gmail.com>
>
>>  For an active/active mode, i'd recommend the use of a load balancer in
>> the frontend and the use of private per service ip addresses in the
>> backend for each node in the cluster.
>> Give a look at,
>>
>> http://www.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/5/html/Virtual_Server_Administration/
>>
>> I think you could use LVS in the same cluster nodes.
>>
>> On 8/10/09, Amos KABORE <amos.kabore at gmail.com> wrote:
>> > Hello,
>> >
>> >
>> >
>> > We have 2 nodes cluster with rhel5.
>> >
>> > Luci is used to manage our cluster (active/active).
>> >
>> >
>> >
>> > Our system includes 3 services (Oracle iAS, Oracle database and
>> E-business
>> > Suite 11i).
>> >
>> > We want to create a unique virtual IP/hostname for these services.
>> >
>> > Is it possible ?
>> >
>> >
>> >
>> > How to create a virtual IP/Hostname in our case ?
>> >
>> >
>> >
>> > As I'm to new to cluster world, your help will be precious.
>> >
>> >
>> >
>> > Thanks
>> >
>> >
>> >
>> > amos.kabore at expercosarl.com
>> >
>> >
>> >
>> >
>> >
>> >
>>
>> --
>> redhat-sysadmin-list mailing list
>> redhat-sysadmin-list at redhat.com
>> https://www.redhat.com/mailman/listinfo/redhat-sysadmin-list
>>
>
>
>
> --
> "Life on Earth may be expensive,
> but it comes with a free ride around the Sun."
>
> --
> redhat-sysadmin-list mailing list
> redhat-sysadmin-list at redhat.com
> https://www.redhat.com/mailman/listinfo/redhat-sysadmin-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listman.redhat.com/archives/redhat-sysadmin-list/attachments/20090814/d7847a0f/attachment.htm>