To create multiple intance

could any one help me for the following question. I am learning Oracle DBA. I am trying to create a multiple instance in a same machine. I could create a first instance in different database name without any problem, i am able to work in SVRMGR. For the second instance with differnt DB name( I dont know whether it is possible), instance is created but I am not able to open the database. What are the parameter that I have to change. How I can connect to the PL/sql in this situation. Pl help me for the above question Thank you very much.

bye
Siva

Siva,

What is the error message you get when you try to open the database?

Gerry

Thanks millerg

Here I have got the following error, when I tried to open and mount the database in the second instance.
This is the first message after giving the
Startup pfile='Parameter file path'
< SGA Information Opened>
ORA-01102 cannot mount database in EXCLUSIVE mode

Then I tried to give Alter database open;
The error message for the above command is;
ORA-01507 Database not mounted;

Thanks for your help
SIva

You are trying to mount the db which is already mounted by other instance.
Have you created the database to be tied with the new instance?
Also make sure that you set the ORACLE_SID to correct instance before starting the new instance.

Sanjay

Are you trying to create a parallel/cluster option?

Sam

Thank you sanjay and Sambavan.
I made misake in Init file. I have given the
same database name for the two instance. I made change in one of the init.ora file.
now I could create two instance in the same machine in two different directories. BUt still, how can I connect to the SQL+(Not thru SVRMGR) parrallely from windows. by default it is connecting to oralce default DB. I hope this is parrallel server option(Am I right?), in this situation how can I connect to the SQL+ from windows, so this is the problem I am facing. Thanks all your help.
Bye
Siva

You can create the services for both the instances using Net8 Configuriation Assistance and connect to it using
sqlplus username/password@servicename
or
set oracle_sid=xyz
sqlplus username/password
Sanjay

thanks Sanjay, I got your point.

bye
Siva