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na_netgroup - Network groups data base




netgroup defines network wide groups used for access permission checking during remote mount request processing. Each line defines a group and has the format:

groupname member-list

Each element in member-list is either another group name or a triple of the form:

(hostname, username, domainname)

The hostname entry must be fully qualified if the specified host is not in the local domain.

The node can also use the netgroup NIS map.

Since the node uses netgroups only in /etc/exports (see na_exports(5)), the username entry is ignored. The domainname field refers to the domain in which the netgroup entry is valid. It must either be empty or be the local domain; otherwise the netgroup entry is ignored. An empty entry allows a single /etc/netgroup file to be used for nodes in multiple domains.

A group definition can be at most 4096 bytes even when `\'s are used to extend the definition over several lines. The maximum nesting level when group names are used in the member-lists of other groups is 1000.

Modifications to the /etc/netgroup file may take upto 60 seconds to take effect.


This is a typical netgroup file:

trusted_hosts (adminhost,,) (zeus,,) (thor,,) (minerva,,)

(sleepy,,) (dopey,,) (grumpy,,) (sneezy,,)
trusted_hosts untrusted_hosts

With this netgroup file it might make sense to modify /etc/exports to export / on the node only to trusted_hosts, but to export /home to all_hosts.


directories and files exported to NFS clients
host name data base


na_exportfs(1), na_hosts(5), na_exports(5), na_nis(8)


The only place that netgroups can be used are in the options of the exportfs command (see exportfs(1)) and /etc/exports.

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