code: 9ferno

ref: 44ce0097b612a1fefd754065bdf8d9d2e5ef60c8
dir: /man/8/dhcpd/

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.TH DHCPD 8
.SH NAME
.B ip/dhcpd
[
.B -ds
] [
.B -f
.I ndbfile
] [
.B -x
.I net
] [
.I ipaddr n ...
]
.SH DESCRIPTION
.B Dhcpd
serves the BOOTP protocol, and DHCP extensions.
.PP
Options:
.TP
.BI -f " ndbfile"
Read configuration from
.I ndbfile
instead of the default
.IR /lib/ndb/local .
.TP
.BI -x " net"
Serve on
.I net
instead of the default
.IR /net .
.TP
.B -d
Print debug information.
.TP
.B -s
Only listen for and print requests, don't respond to them.
.PP
Bootp clients need an explicit
.I ether
entry in the ndb file.
Dhcp clients may have an explicit
.I ether
entry.  Clients that are not explicitly configured will receive an available address from the dynamic address pool.
The pool is specified by parameters to dhcpd, with zero or more pairs of
.I ipaddr
and
.IR n ,
the first ip address of a range and the number of addresses.
Leases are recorded in
.IR /services/dhcpd/,
each leased ip address is stored in a file named after the ip address.
Files in /services/dhcpd/ are read at start up, to ensure leases survive restarts
dhcpd and clients receive the same ip addresses as long
as the pool has unused addresses.
.PP
Clients request an ip address and accompanying configuration (e.g.
gateway, dns servers).  Dhcpd consults the ndb file for the following
options:
.IR ipmask ,
.IR ipgw,
.IR dns ,
.IR sys ,
.IR dnsdomain ,
.IR bootf ,
.IR rootpath ,
.IR leasetime ,
.IR nextserver .
.IR Ndb (6)
defines most of them.
.I Rootpath
is used by clients with a network file system as root.
.I Leasetime
is the DHCP lease time, it defaults to one day.
.I Nextserver
is the server to continue booting from, typically a tftp server that serves a kernel.
.PP
Attributes are resolved by first looking for entries that exactly match the IP address.
.I Ipnet
entries are consulted for the remaining options, most specific
.I ipmask
first.
.SH EXAMPLE
The following is a snippet from a /lib/ndb/local:

.EX
	ipnet=lan ip=192.168.1.0 ipmask=255.255.255.0
		ipgw=192.168.1.254
		dnsdomain=lan
		dns=192.168.1.254
		nextserver=192.168.1.1

	ip=192.168.1.1 sys=narf
	ip=192.168.1.10 sys=laser
	ip=192.168.1.11 sys=wrt54gl

	ip=192.168.1.33 ether=000ae43623bc sys=dis
	ip=192.168.1.34 ether=000ae4269c38 sys=bad
		bootf=9pxeload
	ip=192.168.1.35 ether=000ae432664c sys=yeah
	ip=192.168.1.50 ether=00504301c7d5 sys=sheeva0
		bootf=sheeva0
.EE
.SH SOURCE
.B /appl/cmd/ip/dhcpd.b
.SH FILES
.B /services/dhcpd/
.SH SEE ALSO
.IR ndb (6),
.IR dhcp (8)
.br
Internet RFCs
.IR RFC951 ,
.IR RFC1542 ,
.IR RFC2131 ,
.IR RFC2132
.SH BUGS
Only DHCPv4 support is implemented.