SA changed the host name in addition to the IP address, so things were a little different to recover.  All the below are from the ASM home.

 1.       First, I had to run the following as root:   $GRID_HOME/crs/install/roothas.pl -deconfig -force -verbose

2.       Then, again as root, you have to run $GRID_HOME/root.sh .  you may run into a message saying that RAC was turned off, if so, then you’ll need to run make -f ins_rdbms.mk rac_off as root in $GRID_HOME/rdbms/lib  (if you get “make: 1254-004 The error code from the last command is 1.” follow 1290438.1 from metalink)

3.       After this, make sure you update the $GRID_HOME/network/bin listener with the correct host

4.       Start the listener

5.       Do steps 2-9 below.  The disk groups will auto-mount, but it will take a while.

6.       No need to do steps 10-15