Re: oracle datavbase down

Was the place where your environment variables are set on the disk that crashed? How about oratab - do you know where it is and what is in it?  I'm guessing when you reinstalled oracle it wrote you a new oratab and that only has the settings for one instance. You probably just need to set ORACLE_SID for the other instance, or use oraenv to condition your environment with a proper oratab.

You need to be more specific about your operating system, version of oracle, and any error messages.
There is no single operating system called UNIX. Of the various operating systems, there are many ways to configure oracle and the files needed to bring it up, whether at boot time or later.

Also see http://www.dbaoracle.net/readme-cdos.htm

jg

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