There is a master node for CVM as well as a primary for SFCFS. When growing a file system, you grow the volume from the CVM master, and then grow the file system from any SFCFS node. The CVM master and the SFCFS node can be different nodes.
To determine the primary file system in a cluster
# fsclustadm -v showprimary
mount_point
To determine that the current node is the master CVM node
To actually increase the size of the file system
#
vxassist -g
shared_disk_group
growto
volume_name
newlength
#
fsadm -F vxfs -b
newsize
-r
device_name mount_point