DHCP
Tom
Eastep
2002-11-03
2001
2002
Thomas M. Eastep
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If you want to Run a DHCP Server on your firewall
Specify the dhcp
option on each interface to be
served by your server in the /etc/shorewall/interfaces
file. This will generate rules that will allow DHCP to and from your
firewall system.
When starting dhcpd
, you need to list those
interfaces on the run line. On a RedHat system, this is done by
modifying /etc/sysconfig/dhcpd.
If a Firewall Interface gets its IP Address via DHCP
Specify the dhcp
option for this interface in the
/etc/shorewall/interfaces
file. This will generate rules that will allow DHCP to and from
your firewall system.
If you know that the dynamic address is always going to be in
the same subnet, you can specify the subnet address in the
interface's entry in the /etc/shorewall/interfaces
file.
If you don't know the subnet address in advance, you should
specify detect
for the interface's subnet address
in the /etc/shorewall/interfaces
file and start Shorewall after the interface has started.
In the event that the subnet address might change while
Shorewall is started, you need to arrange for a shorewall
refresh
command to be executed when a new dynamic IP address
gets assigned to the interface. Check your DHCP client's
documentation.