Ignite-UX Administration Guide for HP-UX 11i (B3921-90079, October 2013)

For information regarding creating a DHCP device group for booting anonymous Itanium-based
clients, see “Ignite-UX Server and Boot Helper Setup for DHCP” (page 43).
Using bootptab as an Alternative to DHCP
If you want to have more control over the allocation of IP addresses and their mappings to your
clients, you can configure entries in /etc/bootptab for each client. Because the Bootstrap
Protocol (BOOTP) is a subset of the DHCP protocol, the client's request for a DHCP server will be
satisfied with the BOOTP response.
If you also specify a boot file (bf) of /opt/ignite/boot/boot_lif in the bootptab entries,
you do not need any additional entries in /etc/opt/ignite/inst_boottab. In this case, you
would boot the clients using boot lan instead of boot lan install. Only clients known in
/etc/bootptab will be able to boot if you do not use instl_boottab.
A minimal example /etc/bootptab entry follows; you must use your own hostname, IP address,
hardware address, and subnet mask. Other networking information may also be specified here
or using instl_adm. Specify the Ignite-UX server’s IP address with the instl_adm -t option.
sysname:\
hn:\
vm=rfc1048:\
ht=ether:\
ha=080009352575:\
ip=10.1.51.82:\
sm=255.255.255.0:\
bf=/opt/ignite/boot/boot_lif
NOTE: Important information relevant to using bootptab to enable network installation of clients
is found in “Configuring the Ignite-UX Server for Itanium-Based Clients” (page 34).
Background Information on DHCP Design
The DHCP protocol is implemented as extensions to the BOOTP protocol, and in fact the HP-UX
DHCP server and BOOTP daemons are the same: bootpd. This daemon reads two configuration
files: /etc/bootptab and /etc/dhcptab.
The mapping of systems to IP addresses and lease time information is kept in the DHCP database
file /etc/dhcpdb. Some amount of management of this database is provided by the dhcptools
command.
On the client side, a command called /usr/lbin/dhcpclient is used to contact the server to
get an IP address lease. This command has the ability to broadcast out onto the network prior to
the network interface being enabled.
The dhcpclient also serves as a daemon process that sleeps until such time that it needs to
renew the IP address lease. At that time, the client will recontact the server from which it got the
original lease in order to extend it.
The dhcpclient command is not intended to be run by users directly; it is called by other tools
during system boot and installation.
For more information regarding the networking parameters that DHCP can supply, see
auto_parms(1M) and dhcpdb2conf(1M).
For more general information regarding DHCP, see bootpd(1M) and dhcptools(1M).
234 Configuring DHCP Services