Complete MOS is 2176737.1.
To resize all asm disks then the griddisks that belongs to a disk group after they were created improperly, for example, too small or too large:
#Resize the asm disks
ALTER DISKGROUP <dg> RESIZE ALL SIZE <size>M REBALANCE POWER 64;
For a X6-2 Quarter Rack with 3 cells, in High redundancy, 2TB and 3TB per disk would give diskgroup sizes of 23TB and 35TB.
#2 Resize the griddisks
First check the griddisk names
dcli -g cell_group -l root "cellcli -e list griddisk attributes name,size where name like \'<dg>.*\'"
Then proceed, cell per cell:
dcli -c mycell -l root "cellcli -e alter griddisk <name1>, <name2>,... <name12> SIZE=<size>M"