Using the automount policy

The default delay time for automount is 10. Do not use a value less than 10. To verify the setting of the delay time, use the USS_AUTOMOUNT_DELAY check that is provided by IBM® Health Checker for z/OS®.

Rule: You must keep the automount policy consistent across all the participating systems in the sysplex. The automount facility will not manage any directory until it can process the entire policy without encountering any errors.

Your automount policy most likely resided in the /etc/auto.master and /etc/u.map files. For those using shared file systems, each participating system has a separate /etc file system. In order for the automount policy to be consistent across participating systems, the same copy of the automount policy must exist in every system's /etc/auto.master and /etc/u.map files.

AUTOMOUNT is the preferred method of managing the /u directory. You do not need a mount statement for /u in the BPXPRMxx parmlib member.

For example, both SY1 and SY2 have the following files:

/etc/auto.master
```
 /u     /etc/u.map
```

/etc/u.map

 name       *
 type       ZFS
 filesystem OMVS.<uc_name>.ZFS
 mode       rdwr
 duration   60
 delay      60

When the automount daemon initializes on SY1, it will read its local /etc/auto.master file to identify what directories to manage; in this case, it is /u. Next, the automount daemon will use the policy that is specified in the local /etc/u.map file to mount file systems with the specified naming convention under /u. The automount daemon on SY2 will perform similar actions. Because all mounted file systems are available to all participating systems in the sysplex, your automount policy must be consistent. This is true for the file system name that is specified in /etc/u.map and the values for other parameters in /etc/u.map and /etc/auto.master.

An alternate way of maintaining a consistent automount policy across systems in the file sharing environment is to place the respective files in a common repository. The /global directory in the sysplex root and the file system that has been mounted at this mount point can be used for such a purpose.

Assuming the permission bits of /global have been changed to 7,5,5 after mounting the file system, the following steps can be used.

Create a file called /global/auto.master. This file would be equivalent to the /etc/auto.master file.
Create /global/u.map file and place the automount policy in this file. This file would be equivalent to the /etc/u.map file.
Then, on every system participating in a shared file system, create a symbolic link for /etc/auto.master to /global/auto.master. Also delete each system-specific /etc/u.map file.

This now allows for a single automount policy to reside in a single location in the file sharing environment.