System Administration Guide, Volume 3

How to Customize DHCP Server Performance Options (Command Line)

Changing options using this procedure affect only the current server session. If the DHCP server system is rebooted, the DHCP server starts using the settings specified during server configuration. If you want to change settings to apply to all future sessions, you must run dhcpconfig and answer the prompts as described in "How to Configure a DHCP Server (dhcpconfig) ".

  1. Become superuser on the DHCP server system.

  2. Type the following command:


    # /etc/init.d/dhcp stop
    # /usr/lib/inet/in.dhcpd options
    
    where options are any of the following:
    -h relay-hops

    Specifies the maximum number of relay agent hops that can occur before the daemon drops the DHCP/BOOTP datagram.

    -n

    Disables automatic duplicate IP address detection. This is not recommended.

    -t dhcptab_rescan_interval

    Specifies the interval in minutes that the DHCP server should use to schedule the automatic rereading of the dhcptab information.

    -o seconds

    Specifies the number of seconds the DHCP server should cache the offers it has extended to discovering DHCP clients. The default setting is 10 seconds.

    For example, the following command sets the hop count to 2, disables duplicate IP address detection, sets the rescan interval to 30 minutes, and sets the offer time to 20 seconds.


    # /usr/lib/inet/in.dhcp -h 2 -n -t 30 -o 20