a) When creating a new volume, to determine the largest possible size for a volume, use the following command:
#vxassist -g maxsizeattributes...

For example, to determine the maximum size for a new RAID-5 volume on available disks, use the command:
#vxassist -g maxsize layout=raid5

The output from this command will give the maximum size in sectors.


b) While resizing a volume, to determine how much an existing volume can grow to, use the following command:
#vxassist -g maxgrow

For example, to determine the maximum size that can be achieved by the "datavol" volume in "datadg" diskgroup, below command can be used
#vxassist -g datadg maxgrow datavol

Note: This will not grow the volume, but will give an output stating how much the volume can be grown by.