When you use the pkgadd -a command, the command consults a special administration file for information about how the installation should proceed. Normally, the pkgadd command performs several checks and prompts the user for confirmation before it actually adds the specified package. You can, however, create an administration file that indicates to the pkgadd command that it should bypass these checks and install the package without user confirmation.
The pkgadd command, by default, checks the current working directory for an administration file. If the pkgadd command doesn't find an administration file in the current working directory, it checks the /var/sadm/install/admin directory for the specified administration file. The pkgadd command also accepts an absolute path to the administration file.
Use administration files judiciously. You should know where a package's files are installed and how a package's installation scripts run before using an administration file to avoid the checks and prompts that the pkgadd command normally provides.
mail= instance=overwrite partial=nocheck runlevel=nocheck idepend=nocheck rdepend=nocheck space=nocheck setuid=nocheck conflict=nocheck action=nocheck networktimeout=60 networkretries=3 authentication=quit keystore=/var/sadm/security proxy= basedir=default
Besides using administration files to avoid user interaction when you add packages, you can use them in several other ways. For example, you can use an administration file to quit a package installation (without user interaction) if there's an error or to avoid interaction when you remove packages by using the pkgrm command.
You can also assign a special installation directory for a package, which you might do if you wanted to maintain multiple versions of a package on a system. To do so, set an alternate base directory in the administration file by using the basedir keyword. The keyword specifies where the package will be installed. For more information, see the admin(4) man page.