After checking the prerequisites ("Prerequisites for Maintaining DiskSuite Objects"), and the preliminary information ("Preliminary Information for Expanding Slices and Metadevices"), use the metattach(1M) command to attach additional slices to a RAID5 metadevice. Refer to the metattach(1M) man page for more information.
In general, this is a short-term solution to a RAID5 metadevice running out of space. For performance reasons, it is best to have a "pure" RAID5 metadevice.
# metattach d2 c2t1d0s2 d2: column is attached
For a UFS, run the growfs(1M) command on the RAID5 metadevice. Refer to "How to Grow a File System (Command Line)".
An application, such as a database, that uses the raw metadevice must have its own way of growing the added space.