How to allocate an address to a specific host

[Simon Hobson]

Chiu, PCM (Peter) wrote:
>I have a query about allocating address to a group of specific hosts
>but no one else.
>
>Below is our current set up.
>
>Not sure why hosts other than those in the list are also served with
>this set up.

Because the config says to !


>========================================================================
>===
>option domain-name              "ncas.ac.uk";
>option domain-name-servers      82.66.188.240;
>option subnet-mask              255.255.252.0;
>ddns-update-style ad-hoc;
>subnet 82.66.191.0 netmask 255.255.255.0 {
>range 82.66.191.0 82.66.191.200;
>   option routers 82.66.188.254;
>}
>	group {
>#Insert local ip here \/
>  	next-server 82.66.191.187;          # name of your TFTP server
>  	filename "pxelinux.0";        # name of the bootloader program
>
>	host n0.ral1 {
>		hardware ethernet 00:E0:81:34:0A:4A;
>		fixed-address 82.66.191.187;
>	}
>	host raltes1 {
>                 hardware ethernet 00:E0:81:34:92:18;
>                 fixed-address 82.66.191.50;
>         }
>	host raltes2 {
>                 hardware ethernet 00:E0:81:2F:22:BA;
>                 fixed-address 82.66.191.51;
>         }
>	host raltes3 {
>                 hardware ethernet 00:E0:81:34:0F:B8;
>                 fixed-address 82.66.191.52;
>         }
>	host raltes4 {
>                 hardware ethernet 00:E0:81:34:8D:4C;
>                 fixed-address 82.66.191.53;
>         }
>         host raltes5 {
>                 hardware ethernet 00:E0:81:34:92:62;
>                 fixed-address 82.66.191.54;
>         }
>         host raltes6 {
>                 hardware ethernet 00:E0:81:34:9B:B0;
>                 fixed-address 82.66.191.55;
>         }
>}

You have several errors here :

1) "range 82.66.191.0 82.66.191.200" is not valid as 82.66.191.0 is 
not a valid host address for the subnet.

2) You have fixed address statements with addresses within the 
dynamic range. The server does NOT automatically deal with this - it 
is for the administrator to make them mutually exclusive.

3) If all you want to do is serve up the fixed addresses, then omit 
the range statement - as it stands, you have told it to give certain 
clients fixed addresses, and anything else a dynamic address.

Simon