I recently encountered a VxFS file system that didn’t support largefiles. This issue was causing one of our Oracle databases to complain, which was preventing us from using datafiles optimized for our application access patterns. Since the file system was a Veritas File System (VxFS), I was able to fix this problem with the fsadm utility:
/usr/lib/fs/vxfs/fsadm -F vxfs -o largefiles /u01
mount -p | grep u01
/dev/vx/dsk/oradg/oravol01 - /u01 vxfs - no rw,suid,delaylog,largefiles,ioerror=mwdisable
This operation can be run against mounted live file systems, which is great for production environments.