Overview of the shared file system environment

Start of changeIn a shared file system environment, file systems that are mounted read-only are always sysplex-aware.End of change

Beginning with z/OS® V1R13, zFS runs sysplex-aware on a file system basis (sysplex=filesys). That is, a system running zFS V1R13 or later in a shared file system environment is always capable of mounting zFS read/write file systems as sysplex-aware. The default is to mount all zFS read/write file systems as non-sysplex aware. However, you can specify that you want any individual zFS read/write file system to be sysplex-aware in one of two ways:
  • You can specify the RWSHARE MOUNT PARM.
  • You can specify the sysplex_filesys_sharemode=rwshare zFS configuration option in your IOEFSPRM file. This option sets the default to be that all zFS read/write file systems are sysplex-aware, unless you specify a MOUNT PARM of NORWSHARE to make a specific file system non-sysplex aware.

Beginning with z/OS V1R13, if you specify sysplex=on in your IOEFSPRM file, zFS runs with sysplex=filesys; however, it internally sets the sysplex_filesys_sharemode value to rwshare (if you did not explicitly specify a different sysplex_filesys_sharemode value in your IOEFSPRM file). This behavior makes zFS read/write mounted file systems sysplex-aware by default. Start of changeYou should change your sysplex specification to sysplex=filesys, and you should also specify sysplex_filesys_sharemode=rwshare if you want zFS read/write file systems to be sysplex-aware by default. End of change

The following sections describe how the shared file system environment works using various configurations and the commands for determining the file system owner.

Parent topic: Using zFS in a shared file system environment