hosts -- System Administration

Names and addresses of hosts on the local network
/etc/hosts

The file  /etc/hosts gives the  name and Internet-protocol  (IP) address of
remote hosts with which your system can communicate via a network.

Each line within hosts describes one host on the network.  A description of
a  host begins  with that  host's IP address,  in normal  ``dot'' notation.
This is followed by its name and any aliases it has -- that is, other names
that also refer to that host.  For example, consider the following:

    666.16.16.27    accounting  acctbeancounters
    666.16.16.2 president   boss
    666.16.3.5  engineering

As you  can see, a given  host can have more than  one alias.  Aliases need
not be terse; however, you should  not use an alias name that you would not
want the users of that host to see.

An IP address can appear on more than one line.  For example, entry

    137.229.10.39   raven raven.alaska raven.alaska.edu

can also be rendered as:

    137.229.10.39   raven
    137.229.10.39   raven.alaska
    137.229.10.39   raven.alaska.edu

You may find this to be  more legible.  However, if you need to change this
host's IP  address, you must be  careful to change every  entry, or trouble
will result.

/etc/hosts must include the following standard entries:

     127.1     localhost
     127.0.0.1 loopback

When you  specify only two  parts of an  Internet address, the  second part
represents  the final  three bytes  of that  address.  Thus,  the addresses
127.1 and 127.0.0.1 are, in fact, the same address.

The address 127.1 by convention names the local host.  Packets sent to this
address return to  the local host: they do not  go onto the Ethernet.  This
feature  is useful  in debugging  software.  The  host names  localhost and
loopback are also conventional names for your local host.

/etc/hosts  should also  contain  a separate  entry for  your local  host's
Internet  address and  name.  You  set the  name for  your system  when you
installed  COHERENT.    To  change  your  system's   name,  edit  the  file
/etc/uucpname.

See Also

Adminstering COHERENT,
hosts.equiv,
inetd.conf,
networks,
protocols,
services,
uucpname

© 2012 by Stephen A. Ness