Administrating the 10.2 RAC database in 11.2 Grid CRS

To use the 10.2 Database with 11.2 CRS the the node(s) should be pinned. In 11gR2 default is "unpinned"

Issue below command to check nodes are pinned or not
$GRID_HOME/bin/olsnodes -t -n

If nodes are "unpinned" then to pin nodes by executing the below command as root user
$GRID_HOME/bin/crsctl pin css -n <racnode1> <racnode2>

Also to manage the 10g databases you must use 10g srvctl, you cannot execute the srvctl from 11.2 Grid home

[oracle@coltdb01 db_1]$ /u02/app/11.2.0/grid/bin/srvctl status database -d sendb
PRCD-1027 : Failed to retrieve database sendb
PRCD-1027 : Failed to retrieve database sendb
PRKP-1088 : Failed to retrieve configuration of cluster database sendb
PRKR-1078 : Database sendb of version 10.2.0.0.0 cannot be administered using current version of srvctl. Instead run srvctl from /opt/oracle/product/10.2.0/db_1


Now try from 10.2 database home

[oracle@coltdb01 db_1]$ /opt/oracle/product/10.2.0/db_1/bin/srvctl status database -d sendb
Instance sendb1 is running on node coltdb01
Instance sendb2 is running on node coltdb02