To permit the use of bs2fs file systems, a special area is required in POSIX which temporarily stores the files of bs2fs file systems: the bs2fs container. This is a ufs file system which is explicitly identified as the bs2fs container. Only one single bs2fs container can exist in a POSIX system. This bs2fs container accommodates all the files of all mounted bs2fs file systems.
You can create a file system with the property bs2fs container using the POSIX installation program when installation takes place.
Its size should be defined in accordance with the size of the files actually used. As it can be assumed that not all BS2000 files will be opened at the same time and therefore copied into the container, you could, for example, estimate the space required in the container as follows: multiply the sum of the sizes of all BS2000 files which are mounted with bs2fs by 0.5.
Creating the bs2fs container using the POSIX installation program
When append is specified for a new ufs file system or an existing file system (with
overwrite=yes) together with the bs2fscontainer option, this file system is internally
assigned the property bs2fs container which is required to enable this file system to be
used as the bs2fs container.
Mounting the bs2fs container using the POSIX installation program
Like any other ufs file system, the bs2fs container (= ufs file system with the property bs2fscontainer) can be mounted in the file system hierarchy when Automount=Y is specified. The Automount=Y entry which is then created in the file system table /etc/vfstab also causes the file system to be mounted automatically when the POSIX subsystem is started.
Mounting the bs2fs container during ongoing operation using the mount command
To mount the bs2fs container, enter a corresponding mount command with the
-o bs2fscontainer option, e.g.
mount -F ufs -o bs2fscontainer /dev/dsk/23 /home/bach/mount2
A prerequisite for mounting a file system as the bs2fs container is that it has been created as described under "Creating the bs2fs container using the POSIX installation program", otherwise a mount command with the -o bs2fscontainer option is rejected.
A bs2fs container is by default empty when it is mounted. If it is not empty, its contents are deleted when it is mounted.