Novell LINUX ENTERPRISE SERVER 10 - INSTALLATION AND ADMINISTRATION 11-05-2007, Installation Manual

Page: 647 / 982

Line 10:
The MX record specifies the mail server that accepts, processes, and forwards e-
mails for the domain
world.cosmos
. In this example, this is the host
sun.world.cosmos
. The number in front of the hostname is the preference
value. If there are multiple MX entries, the mail server with the smallest value is
taken first and, if mail delivery to this server fails, an attempt is made with the next
higher value.
Lines 12–17:
These are the actual address records where one or more IP addresses are assigned
to hostnames. The names are listed here without a
.
because they do not include
their domain, so
world.cosmos
is added to all of them. Two IP addresses are
assigned to the host
gateway
, because it has two network cards. Wherever the
host address is a traditional one (IPv4), the record is marked with
AAAA
. If the ad-
dress is an IPv6 address, the entry is marked with
AAAA 0
. The previous token
for IPv6 addresses was only
AAAA
, which is now obsolete.
NOTE: IPv6 Syntax
A IPv6 record has a slightly different syntax than IPv4. Because of the
fragmentation possibility, it is necessary to provide information about
missed bits before the address. You must provide this information even if
you want to use a completely unfragmented address. For the IPv4 record
with the syntax
pluto IN AAAA 2345:00C1:CA11:0001:1234:5678:9ABC:DEF0
pluto IN AAAA 2345:00D2:DA11:0001:1234:5678:9ABC:DEF0
You need to add information about missing bits in IPv6 format. Because
the example above is complete (does not miss any bits), the IPv6 format
of this record is:
pluto IN AAAA 0 2345:00C1:CA11:0001:1234:5678:9ABC:DEF0
pluto IN AAAA 0 2345:00D2:DA11:0001:1234:5678:9ABC:DEF0
Do not use IPv4 addresses with IPv6 mapping.
Line 18:
The alias
www
can be used to address
mond
(
CNAME
means canonical name).
The Domain Name System 629