Novell LINUX ENTERPRISE SERVER 10 - INSTALLATION AND ADMINISTRATION 11-05-2007, Руководство по установке

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The pseudodomain
in-addr.arpa
is used for the reverse lookup of IP addresses
into hostnames. It is appended to the network part of the address in reverse notation.
So
192.168.1
is resolved into
1.168.192.in-addr.arpa
. See Example 33.7,
“Reverse Lookup” (page 630).
Example 33.7 Reverse Lookup
$TTL 2D
1.168.192.in-addr.arpa. IN SOA gateway.world.cosmos. root.world.cosmos. (
2003072441 ; serial
1D ; refresh
2H ; retry
1W ; expiry
2D ) ; minimum
IN NS gateway.world.cosmos.
1 IN PTR gateway.world.cosmos.
2 IN PTR earth.world.cosmos.
3 IN PTR mars.world.cosmos.
Line 1:
$TTL defines the standard TTL that applies to all entries here.
Line 2:
The configuration file should activate reverse lookup for the network
192.168.1.0
. Given that the zone is called
1.168.192.in-addr.arpa
,
should not be added to the hostnames. Therefore, all hostnames are entered in their
complete form—with their domain and with a
.
at the end. The remaining entries
correspond to those described for the previous
world.cosmos
example.
Lines 3–7:
See the previous example for
world.cosmos
.
Line 9:
Again this line specifies the name server responsible for this zone. This time,
however, the name is entered in its complete form with the domain and a
.
at the
end.
Lines 11–13:
These are the pointer records hinting at the IP addresses on the respective hosts.
Only the last part of the IP address is entered at the beginning of the line, without
630 Installation and Administration