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
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Background Information on DHCP Design |
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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).