ORACLE APPLICATION SERVER 11i with MC/ServiceGuard

[Ahmed ABDOU_1]

I have 2 rp8400 HP-UX 11i servers connected to EMC calrion. MC/SG to be used as a cluster of 2 packages. one pkg for each node. The Oracle engineer is asking me to get 2 RIP relocatable IP addresses, one IP for each package. He needs to use DNS to resolve the IP addresses. Then he asked for dynamic hosting, that the machine hostname will be resolved to the RIP address (Relocatable IP address of the package). As per him this is called dynamic hosting, could you please help in this.and how to do it.
Regards

[Jeff Schussele]

Hi Mohammed,

What he's aking for is a virtual-IP for each pkg.
This is standard stuff for MC/SG.
What you do is define the IP in the package control file - EX:
IP[0]=207.111.222.111
SUBNET[0]=207.111.222.0
Then this IS the virtual(dynamic) IP for this pkg & it will be asserted by the actual host running that pkg at the time.

To get it in DNS - give it a name - some name that ties it to the pkg for clarity & put THAT in DNS & then it will be resolved to the actual host running that pkg.
The virtual IP is NOT tied to a host - it's tied to an MC/SG pkg. Whichever host is running the pkg will be asserting THAT IP.

HTH,
Jeff

[melvyn burnard]

I suggest you have a read of the Managing MC/ServiceGuard manual at
http://docs.hp.com/hpux/ha

It is all explained in there.

[Ahmed ABDOU_1]

Dear All,

Dynamic hosting for OAS is different from what you are telling. For example, the 1st machine will boot using hostname that physically assigned to the primary network card, and say it is
100.0.0.1 hostA hostA.stcbss.com
and the Virtual IP address and name of the package is
100.0.0.3 oracle oracle.stcbss.com.
and for the 2nd machine
100.0.0.2 hostB hostB.stcbss.com

When OAS is installed say on hostA, all refrences to hostname in the config files is to hostA. So if the package moved to hostB,
the clients will not be able to connect to oracle. for clients of OAS, the hostname should be oracle that is the package name and this will contradict what is written in the OAS config files. this is my case. need your advice.
Regards

[John Poff · Accepted solution]

Hello,

We do it here, and the solution is to assign a hostname to the package IP address, and put that entry into your /etc/hosts file. Your Oracle application can resolve to that hostname which will go with the package to whichever node runs that package. Your DNS can also resolve the package hostname to the package IP address and work just fine.

JP

[Ashwani Kashyap]

Either you can have all refrences in the config files change from hostname to package name or in the /etc/hosts file put the hostname as an alias to the package name .

[Tom Danzig]

The IP address assigned to the packages are "virtual" IP's. The IP address of the host never changes. Utilizing IP multiplexing, additional IP's are assigned to the same NIC card. This allows MC/SG to switch the IP address of the package from host to host.

You should assign the virtual IP's based on package name and add DNS resolvable entries as appropriate for your name resolution environment. For example:

Pkg1@you.domain.com 10.2.1.250
Pkg2@you.domain.com 10.2.1.251

Does that clear things up a bit?

[Jeff Schussele]

Hi (again) Mohammed,

Don't confuse the system hostname/IP - which NEVER changes - with the MC/SG package name/IP.
And DON'T let the application people use the system hostname or IP. They MUST use the pkg name & IP.

Seems you're letting semantics confuse you. It appears to me what you're defining as a RIP is in fact what we all call virtual IP. It's virtual because it *could* be on ANY node in the cluster defined to run that pkg. That's WHY the applications NEED to be using the virtual IP - so they can be assured of communicating with the proper host that's actually running the pkg. NOT the host they *think* should be running it.

How you resolve the pkg host/IP - via hosts file, DNS, etc. is entirely up to you. But I always recommend DNS for ease of admin alone.

Rgds,
Jeff

[Ahmed ABDOU_1]

Hi Poff,

When you said "We do it here", did you implement OAS with MC/SG. and if so, was it tat simple to add entry for the package IP address and name in /etc/hosts?

Hi Kashyap,

If I take the 1st option: modify all occurences of hostname (hostA) in OAS config files to be "oracle" the package name. And I started the package, so the IP address will be available for OAS, will OAS start working fine?

If take the 2nd option: do you mean to have like this entry in /etc/hosts:

100.0.0.3 oracle oracle.stcbss.com hostA.stc.com
But I must use DNS, so how to make an alias?

Hi Danzig,

I could not get your point, can you simlfy it more?

Hi Schussele,

I need to ask you about DNS:

You know, I will have 2 packages, the 1st one " the application server" to be initially started on hostA, and the 2nd package "database" to be started on hostB. I must use DNS, will this startegy work?
1. configure primary DNS on hostA, and make hostB as secoendary and client DNS.
Regards
Mohammed