Planning disk space is different for everyone; however, here are some basic considerations:
Allocate additional disk space for each language selected (for example, Chinese, Japanese, Korean).
Allocate additional disk space in the /var file system if printing or mail support is planned.
Allocate additional disk space in the /var file system if use of the crash dump feature is planned. For information about the crash dump feature, see System Administration Guide, Volume I.
Allocate additional disk space on a server if it's going to provide home file systems for users on other systems (by default, home directories are usually located in the /export file system).
Allocate additional disk space on an OS server for diskless clients or Solstice AutoClient systems. The Solaris Interactive Installation program enables you to allocate space for these systems (by default, disk space is allocated in the /export file system).
Make sure you allocate enough swap space. See Table 8-4 for information about how much swap space you should allocate on a system.
Allocate space for the Solaris software group that you want to install. See "Software Group Space Recommendations" for recommended disk space for the software groups. When planning disk space, remember that the installation program enables you to add or remove individual software packages from the software group that you select.
Create a minimum number of file systems. By default, the Solaris Interactive Installation program creates only root (/), /usr, and swap (/export is also created when space is allocated for OS services). Creating a minimum number of file systems helps with future upgrades and file system expansion, because separate file systems are limited by their slice boundaries.
Allocate additional disk space for co-packaged or third-party software.