NAME
dhcpd, dhcpleases, tftpd – Internet booting |
SYNOPSIS
ip/dhcpd [–dmnprsSZ] [–f ndb–file] [–M secs] [–x netmtpt] [–Z secs]
[ address n ] ... ip/dhcpleases
ip/tftpd [–dr] [–h homedir] [–x netmtpt] |
DESCRIPTION
These programs support booting over the Internet. They should
all be run on the same server to allow other systems to be booted.
Dhcpd and tftpd are used to boot everything.
Dhcpd runs the BOOTP and DHCP protocols. Clients use these protocols
to obtain configuration information. This information comes from
attribute/value pairs in the network database (see ndb(6) and
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:
A BOOTP request is honored if all of the following are true:
Dynamic addresses are specified on the command line as a list
of addresses and number pairs. For example,
Dhcpd maintains a record of all dynamic addresses in the directory /lib/ndb/dhcp, one file per address. If multiple servers have access to this common directory, they will correctly coordinate their actions.
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:
Dhcpd will answer 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 dhcpd to answer. Dhcpd
will answer all DHCP requests for which it can associate an IP
address with the requester. The options are: Dhcpleases prints out the currently valid DHCP leases found in the /lib/ndb/dhcp directory.
Tftpd transfers files to systems that are booting. It runs as
user none and can only access files with global read permission.
%C in a file name is replaced with the name of the booting system's
/cfg/pxe file. Similarly, %E becomes the booting system's Ethernet
MAC address and %I becomes its IP address. The
options are:
|
FILES
/lib/ndb/dhcp directory of dynamic address files |
SOURCE
/sys/src/cmd/ip |
SEE ALSO
ndb(6), 9boot(8), booting(8) |
BUGS
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. |