[Linux-HA] Cloning heartbeat::ocf:IPaddr with different IPs

[Michael Schwartzkopff]

Christian Rishøj schrieb:
> On 6/16/07, Michael Schwartzkopff <misch at multinet.de> wrote:
>> > Is it possible to set up cloning of heartbeat::ocf:IPaddr resources,
>> > where each clone has a separate IP address?
>>
>> No,
>> clones are identical, except the clone instance number.
>> But you could develop your own myIPaddr resource agent that computes the
>> IP address from a base address plus the instance number.
>
> Interesting option. How can I retrieve the instance number in the
> resource agent?
>
See:
http://www.linux-ha.org/v2/Concepts/Clones
section: Requirements for ResourceAgents

> And a more general clustering question: It is stated somewhere in the
> documentation that clones were made for the purpose of IP adresses.
> Now, wouldn't most routers prohibit usage of the same IP address on
> several nodes? What is the common idiom in this case?


Use multicast MAC Adresses. And yes, some routers do not learn multicast
MAC addresses. You would have to configure these addresses statically. I
wrote an  article about that (CLUSTERIP target of iptables) in the
German "Linux Magazin". It will be published in the English version
soon. For the use of CLUSTERIP in a Linux-HA RA see:
http://www.linux-ha.org/ClusterIP

Michael.