Convert an Oracle 10g RAC database to single instance

Solved! The trick is to re-register the instance resource. As root:

crs_stat -p ora.db.instance1.inst > /tmp/ora.db.instance1.inst.cap

Edit /tmp/ora.db.instance1.inst.cap and add the vip resource to REQUIRED_RESOURCES

Run:

crs_register ora.db.instance1.inst -d /tmp -u

the "-u", I'm guessing is update, does the magic. After that you need to re set permission (or maybe run the whole thing as "oracle" user)

crs_setperm ora.db.instance1.inst -o oracle
crs_setperm ora.db.instance1.inst -g dba
crs_setperm ora.db.instance1.inst -u pgrp:dba:rwx

That's it. Run a

crs_stat -p crs_stat -p ora.db.instance1.inst

to make sure the changes have been saved and restart the instance

This is relevent to 10.2.0.4

Your database is looping as it attempt to do a recovery and bring undo segments back online to recover your database. Since you are not a dba, I would immediately get oracle support on the line and tell them that you need major assistance and that you are not a dba. They will very likely have you startup the database and disable the recovery manager that is having smon loop trying to clean up undo segments. Having had to do undo segment cleanup in the past, it is best done with oracle supports help. Much of the steps will require some events and underscore parameters that disable/enable hidden oracle mojo. I would not recommend attempting anything you find on your own or is posted without understanding the implication and possibly how to recover/back out of your attempts. The object is to recover your database and not make it worse. Get oracle support on the phone asap.