Single machine — A fully qualified domain name (that can
be resolved by the server), hostname (that can be resolved by the
server), or an IP address
Series of machines specified with wildcards — Use the *
or ? character to specify a string match. Wildcards are not to be
used with IP addresses; however, they may accidentally work if
reverse DNS lookups fail. When specifying wildcards in fully
qualified domain names, dots (.) are not included in the wildcard.
For example, *.example.com
includes one.example.com but does not include
one.two.example.com.
IP networks — Use a.b.c.d/z,
where a.b.c.d is the network and
z is the number of bits in the netmask
(for example 192.168.0.0/24). Another acceptable format is
a.b.c.d/netmask, where
a.b.c.d is the network and
netmask is the netmask (for example,
192.168.100.8/255.255.255.0).
Netgroups — In the format
@group-name, where
group-name is the NIS netgroup
name.