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.TH DHCPD 8

.SH NAME

dhcpd, dhcpleases, rarpd, tftpd \- Internet booting

.SH SYNOPSIS

.PP

.B ip/dhcpd

.RB [ -dmnprsSZ ]

.RB [ -f

.IR ndb-file ]

.RB [ -M

.IR secs ]

.RB [ -x

.IR netmtpt ]

.RB [ -Z

.IR secs ]

[

.I address

.I n

] ...

.PP

.B ip/dhcpleases

.PP

.B ip/rarpd

.RB [ -d ]

.RB [ -e

.IR etherdev ]

.RB [ -x

.IR netmtpt ]

.PP

.B ip/tftpd

.RB [ -dr ]

.RB [ -h

.IR homedir ]

.RB [ -x

.IR netmtpt ]

.SH DESCRIPTION

These programs support booting over the Internet.

They should all be run on the same server to

allow other systems to be booted.

.I Dhcpd

and

.I tftpd

are used to boot everything;

.I rarpd

is an extra piece just for Suns.

.PP

.I Dhcpd

runs the

.SM BOOTP

and

.SM DHCP

protocols.

Clients use these protocols to obtain configuration information.

This information comes from attribute/value pairs in the network database

(see

.IR ndb (6)

and

.IR ndb (8)).

DHCP requests are honored both for static addresses found in

the NDB and for dynamic addresses listed in the command line.

DHCP requests are honored if either:

.br

\- there exists an NDB entry

containing both the ethernet address of the requester and

an IP address on the originating network or subnetwork.

.br

\- a free dynamic address exists on the originating network or subnetwork.

.PP

A BOOTP request is honored if all of the following are true:

.br

\- there exists an NDB entry

containing both the ethernet address of the requester and

an IP address on the originating network or subnetwork.

.br

\- the entry contains a

.B bootf=

attribute

.br

\- the file in the

.B bootf=

attribute is readable.

.PP

Dynamic addresses are specified on the command line as a list

of addresses and number pairs.

For example,

.EX

	ip/dhcpd 10.1.1.12 10 10.2.1.70 12

.EE

directs

.I dhcpd

to return dynamic addresses 10.1.1.12 through 10.1.1.21 inclusive

and 10.2.1.70 through 10.2.1.81 inclusive.

.PP

.I Dhcpd

maintains a record of all dynamic addresses in the directory

.BR /lib/ndb/dhcp ,

one file per address.

If multiple servers have access to this common directory,

they will correctly coordinate their actions.

.PP

Attributes come from either the NDB entry for the system, the entry for its

subnet, or the entry for its network.  The system entry has precedence,

then the subnet, then the network.

The NDB attributes used are:

.TF ipmask

.TP

.B ip

the IP address

.TP

.B ipmask

the IP mask

.TP

.B ipgw

the default IP gateway

.TP

.B dom

the domain name of the system

.TP

.B fs

the default Plan 9 name server

.TP

.B auth

the default Plan 9 authentication server

.TP

.B dns

a domain name server

.TP

.B ntp

a network time protocol server

.TP

.B time

a time server

.TP

.B wins

a

.SM NETBIOS

name server

.TP

.B www

a World Wide Web proxy

.TP

.B pop3

a POP3 mail server

.TP

.B smtp

an SMTP mail server

.TP

.B bootf

the default boot file;

see

.IR ndb (6)

.PD

.PP

.I Dhcpd

will answer

.SM BOOTP

requests only if it has been specifically targeted or if it

has read access to the boot file for the requester.  That means that the requester

must specify a boot file in the request or one has to exist in NDB for

.I dhcpd

to answer.

.I Dhcpd

will answer all

.SM DHCP

requests for which it can associate an IP address with the

requester.

The options are:

.TP

.B d

Print debugging to standard output.

.TP

.B f

Specify a file other than

.B /lib/ndb/local

as the network database.

.TP

.B m

Mute: don't reply to requests, just log them and what

.I dhcpd

would have done.

.TP

.B M

Use

.I secs

as the minimum lease time for dynamic addresses.

.TP

.B n

Don't answer

.SM BOOTP

requests.

.TP

.B p

Answer

.SM DHCP

requests from

.SM PPTP

clients only.

.TP

.B r

Mute static addresses: don't reply to requests for static addresses,

just log them and what

.I dhcpd

would have done.

.TP

.B s

Sleep roughly 1 to 2 seconds before answering requests for static addresses.

This is used to make a server be a backup only.

.TP

.B S

Sleep roughly 1 to 2 seconds before answering requests for dynamic addresses.

.TP

.B x

The IP stack to use is mounted at 

.IR netmtpt .

The default is

.BR /net .

.TP

.B Z

Use

.I secs

as the minimum lease time for static addresses.

.PD

.PP

.I Dhcpleases

prints out the currently valid DHCP leases found in the

.B /lib/ndb/dhcp

directory.

.PP

.I Rarpd

performs the Reverse Address Resolution Protocol, translating

Ethernet addresses into IP addresses.

The options are:

.TP

.B d

Print debugging to standard output.

.TP

.B e

Use the Ethernet mounted at

.BI /net/ etherdev\f1.

.TP

.B x

The IP stack to use is mounted at 

.IR netmtpt .

The default is

.BR /net .

.PD

.PP

.I Tftpd

transfers files to systems that are booting.

It runs as user

.B none

and can only access files with global read permission.

.L %C

in a file name is replaced with the name of the

booting system's

.L /cfg/pxe

file.

Similarly,

.L %E

becomes the booting system's Ethernet MAC address

and

.L %I

becomes its IP address.

The options are:

.TP

.B d

Print debugging to standard output.

.TP

.B x

The IP stack to use is mounted at 

.IR netmtpt .

The default is

.BR /net .

.TP

.B h

Change directory to

.IR homedir .

The default is

.BR /lib/tftpd .

All requests for files with non-rooted file names are served starting at this

directory with the exception of files of the form

.BR xxxxxxxx.SUNyy .

These are Sparc kernel boot files where

.B xxxxxxxx

is the hex IP address of the machine requesting the kernel and

.B yy

is an architecture identifier.

.I Tftpd

looks up the file in the network database using

.I ipinfo

(see

.IR ndb (2))

and responds with the boot file specified for that particular

machine.

If no boot file is specified, the transfer fails.

.I Tftpd

supports only octet mode.

.TP

.B r

Restricts access to only those files rooted in the

.IR homedir .

.PD

.SH FILES

.BR /lib/ndb/dhcp "    directory of dynamic address files

.SH SOURCE

.B /sys/src/cmd/ip

.SH "SEE ALSO"

.IR ndb (6),

.IR 9boot (8),

.IR booting (8)

.SH BUGS

.I Dhcpd

doesn't really understand a single interface having addresses

on multiple subnets, as during renumbering of a subnet.

It will only respond with addresses on the subnet

of its primary IP address on that interface.