Red Hat ENTERPRISE LINUX 4 System Administration Manual page 227

Figure 21.2. Add Share
The General Options tab allows the following options to be configured:
• Allow connections from port 1024 and higher — Services started on port numbers less than
1024 must be started as root. Select this option to allow the NFS service to be started by a user
other than root. This option corresponds to insecure.
• Allow insecure file locking — Do not require a lock request. This option corresponds to
insecure_locks.
• Disable subtree checking — If a subdirectory of a file system is exported, but the entire file system
is not exported, the server checks to see if the requested file is in the subdirectory exported. This
check is called subtree checking. Select this option to disable subtree checking. If the entire file
system is exported, selecting to disable subtree checking can increase the transfer rate. This option
corresponds to no_subtree_check.
• Sync write operations on request — Enabled by default, this option does not allow the server
to reply to requests before the changes made by the request are written to the disk. This option
corresponds to sync. If this is not selected, the async option is used.
• Force sync of write operations immediately — Do not delay writing to disk. This option
corresponds to no_wdelay.
The User Access tab allows the following options to be configured:
• Treat remote root user as local root — By default, the user and group IDs of the root user
are both 0. Root squashing maps the user ID 0 and the group ID 0 to the user and group IDs of
anonymous so that root on the client does not have root privileges on the NFS server. If this option
is selected, root is not mapped to anonymous, and root on a client has root privileges to exported
directories. Selecting this option can greatly decrease the security of the system. Do not select it
unless it is absolutely necessary. This option corresponds to no_root_squash.
• Treat all client users as anonymous users — If this option is selected, all user and group IDs are
mapped to the anonymous user. This option corresponds to all_squash.
Exporting NFS File Systems
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