dhcp.conf

[Tim]

On Wed, 2006-12-20 at 17:42 +0900, Shawn wrote:
> Trying to get dhcp to work in fc6, I would need a client right?

If you're a client of another DHCP server, yes.  Not if you're running
the box as a DHCP server.

> In fc3, lookup worked out of the box; but in my fc6 install I didn't
> have the rpm installed.

FC6 works as a DHCP client out of the box, for me.  If I wanted it to be
a DHCP server, I'd have to install the extra package.

> Now that I do, I need a dhcpd.conf

That's for a server configuration.

> If I do need one, can I just ask a few questions.

What are you trying to do?

Use DHCP to configure this PC by your router or ISP?  You want a client.

Or use DHCP on your PC to configue other PCs?  You want a server.

> # Sample dhcpd.conf
> 
> # option definitions common to all supported networks...
> #option domain-name "linuxhelp.ca";
> ??I don't have a domain on this box so no need I think

Not sure if you *need* a domain name, but various things will insist on
addresses resolving to a fully-qualified domain name (i.e. a short
hostname isn't good enough for *them*).

> # Your name servers. You can normally find these in 
> # your /etc/resolv.conf file. These will be distributed to all DHCP 
> # clients.
> option domain-name-servers 10.1.1.1, 65.39.196.215, 65.39.192.130;
> 
> ?? what is 10.1.1.1????  I have two entries 210.230.70.2 210.230.70.3
> plus a name "rosenet.ne.jp"
> ??does rosenet.ne.jp translate into a number somehow using a command
> like host or um forgot the other reverse lookup

10.1.1.1 is an address that might be used on a LAN.  This is an example
configuration file that you're looking at.  It's giving you hints about
how it might be used.  It won't be of much use to you to directly use it
as it is.

The option domain-name-servers is a list of addresses for DNS servers
that the DHCP server will pass on to clients for them to use.

"nslookup" and "dig" are two commands that you can use to look up
addresses.

> default-lease-time 600;
> max-lease-time 7200;
> ??sure fine, copy and paste - values ok?

Those are time limits, in seconds.  By default, leases will be offered
that'll last 600 seconds (10 minutes).  Clients can ask for a different
lease period, and you've got a maximum set of 7200 seconds (leases won't
be offered for a longer period than that).  Before the expiry time,
clients will renegotiate for another lease.  They're quite okay values
to use.

> # If this DHCP server is the official DHCP server for the local
> # network, the authoritative directive should be uncommented.
> authoritative;
> ??for the local network of one box yes. no?

For any box on the same LAN as it.  There should only be one DHCP server
answering queries on a network.  Or, if there's more than one, they have
to be networked together in a co-operative manner.

> # Configuration for an internal subnet.
> subnet 10.1.1.0 netmask 255.255.255.0 {
>   range 10.1.1.2 10.1.1.25;
>   option domain-name-servers 10.1.1.1, 65.39.196.215, 65.39.192.130;
>   option domain-name "linuxhelp.ca";
>   option routers 10.1.1.1;
>   option broadcast-address 10.1.1.255;
>   default-lease-time 600;
>   max-lease-time 7200;
> }
> 
> ?? um internal subnet.  again this is just one box.  Do I need to
> configure this.  Can I get the info from my fc3 box running dhcp fine
> somehow?

Okay, just one box?  I think that you don't want to configure a DHCP
server.  You want to configure your box to be a client.

What is your network?  One box and a router?  One box and your ISP?

> My fc3 dchp.conf file is in a totally different place and seems vastly different:

Things change.  I can't even remember how FC3 was configured.

On FC4/5/6, as far as I'm aware, a DHCP server is configured
by /etc/dhcpd.conf, and a DHCP client by /etc/dhclient-eth0.conf (where
the "eth0" bit is replaced by whatever network adaptor it works with).

You might want to read through:
 man dhclient
 man dhclient.conf
 man dhcp
 man dhcpd.conf