bootpd.1m (2010 09)

ManualsBrandsHP ManualsSoftwareHP-UX Manpages

bootpd(1M) bootpd(1M)

NAME

bootpd - Internet Boot Protocol server

SYNOPSIS

/usr/lbin/bootpd

[-a][-d debuglevel ][

-p ping-timeout ][-t timeout ][-P][conﬁgﬁle

[dumpﬁle ]]

DESCRIPTION

The

bootpd daemon implements three functions: a Dynamic Host Conﬁguration Protocol (DHCP) server

as deﬁned in RFC1541, an Internet Boot Protocol (BOOTP) server as deﬁned in RFC951 and RFC1395,

and a DHCP/BOOTP relay agent as deﬁned in RFC1542. It also contains some of the useful ﬁelds as

deﬁned in RFC2132.

bootpd is run through inetd (see inetd (1M)). It is run by

/etc/inetd when the following line (or

equivalent) is included in the ﬁle

/etc/inetd.conf

bootps dgram udp wait root /usr/lbin/bootpd bootpd

Options

-t bootpd starts when a boot request arrives. If it has not received another boot request after

500 minutes, bootpd exits. The -t

option can be used to specify a different timeout value in

minutes (such as

-t20). With a timeout value of zero (-t0), bootpd

never exits.

-a The -a option enables the bootpd server to accept valid short packets (300

> packet size >

244).

-d The -d option sets the verbosity level (1−3) of the logging emitted by the daemon via

syslog

(see syslog (3C)). For improved performance, this option should not be used. If this option is

not used, no logging is done by syslog except for fatal errors.

-P By default, the bootpd daemon pings the IP address before assigning the address to a client

to check if the IP Address is already in use. The -P option suppresses bootpd from pinging

this address.

-p The -p option can be used to specify the ping timeout period. The server pings for this dura-

tion of time to check if the IP address is already in use. The ping-timeout period is speciﬁed in

milliseconds and the maximum value is 3000 milliseconds. When the

-P option is used, the

-p option has no effect, since bootpd never pings the IP address.

When

bootpd receives a DHCP/BOOTP request, it ﬁrst checks if the hardware address of the client is

listed in the /etc/dhcpdeny database. If yes, this client is denied lease. If the client is not listed in

the

dhcpdeny database, it checks whether the client information is in the /etc/bootptab

database.

If the client information is available,

bootpd sends back the reply. Otherwise, it checks whether there

is any matched relay information for the client in the /etc/bootptab

database. If so, bootpd goes

through a series of checks to see if it should relay the request. If no matched relay information was

found,

bootpd checks whether the client information is matched by a pool or device group in the

/etc/dhcptab database. If a match is found, bootpd sends back a reply. The request is dropped if

no matched group information is found.

To reply to a DHCP or BOOTP request the server puts together a BOOTREPLY message and does a

number of checks to ensure the message is sent to the correct destination.

bootpd ﬁrst checks the ciaddr (client IP address) ﬁeld of the DHCP/BOOTP packet. If this ﬁeld is

nonzero, the BOOTREPLY message is sent to the IP address identiﬁed in ciaddr.

If the

ciaddr ﬁeld is zero, bootpd checks the giaddr ﬁeld. If this ﬁeld is not zero, bootpd sends the

BOOTREPLY message to the relay agent speciﬁed in giaddr ﬁeld and the relay agent delivers the BOO-

TREPLY message to the client. If the giaddr ﬁeld is zero, bootpd sends the BOOTREPLY message to

the client. In both cases, the BOOTREPLY will either be sent to the IP address speciﬁed in the yiaddr

(your IP address) ﬁeld or as a broadcast message. On HP-UX, there are two ways to specify that the

BOOTREPLY should be sent as a broadcast message.

1. The client sets the broadcast ﬂag bit in the ﬂag ﬁeld (bit 0) of the DHCP/BOOTP request packet.

2. Deﬁne the

ba tag in the bootptab ﬁle (see Tags for client entries below)

For the case where the

bootpd has matched a relay entry in /etc/bootptab, it attempts to forward

the request to the conﬁgured DHCP/BOOTP server.

HP-UX 11i Version 3: September 2010 − 1 − Hewlett-Packard Company 1

Summary of content (14 pages)

PAGE 1
bootpd(1M) bootpd(1M) NAME bootpd - Internet Boot Protocol server SYNOPSIS /usr/lbin/bootpd [-a] [-d debuglevel ] [-p ping-timeout ] [-t timeout ] [-P] [configfile [dumpfile ] ] DESCRIPTION The bootpd daemon implements three functions: a Dynamic Host Configuration Protocol (DHCP) server as defined in RFC1541, an Internet Boot Protocol (BOOTP) server as defined in RFC951 and RFC1395, and a DHCP/BOOTP relay agent as defined in RFC1542. It also contains some of the useful fields as defined in RFC2132.
PAGE 2
bootpd(1M) bootpd(1M) bootpd first checks whether the relay function is enabled for the requesting client. The relay capability is configurable. If the relay function is disabled, then the request packet is dropped. Before bootpd relays the request, it also examines the giaddr (gateway IP address) field. The client sets the giaddr field to zero when it sends out the request.
PAGE 3
bootpd(1M) bootpd(1M) 3. The tags that can only be used in the client information entries. Tag ip is used to differentiate a client entry from a relay entry. An entry with tag ip defined is treated as a client entry. A relay entry can contain the relay configuration for an individual client, also a hardware address mask mechanism is provided to configure the relay entry for a group of clients. The group client relay entries are kept in a linear sorted table by bootpd.
PAGE 4
bootpd(1M) bootpd(1M) else continue the search Tags for client entries ba This tag specifies that bootpd should broadcast the boot reply to the client. As a boolean tag, it causes bootpd to send the boot reply on the configured broadcast address of each network interface. You can also assign the tag an IP-address value, which specifies the specific IP or broadcast address for the boot reply. bf=filename A This tag specifies the filename of the bootfile that the client should download.
PAGE 5
bootpd(1M) bootpd(1M) ef=filename Specifies the name of an extensions file. The file, retrievable via TFTP, contains information which can be interpreted in the same way as the 64-octet vendor-extension field within the BOOTP response. The maximum length of the file is unconstrained. All references to an extensions filename within the file are ignored. gw=ip_address_list This tag specifies the IP addresses of gateways for the client’s subnet.
PAGE 6
bootpd(1M) bootpd(1M) ps=ip_address_list This tag specifies the IP address(es) of NIS+ servers available to the client (RFC2132). rl=ip_address_list This tag specifies the IP addresses of RFC887 Resource Location Protocol servers. rp=root_path This tag specifies a path name to be mounted as a root disk. sa=tftp_server A This tag specifies the IP address of the TFTP server where the client’s bootfile resides.
PAGE 7
bootpd(1M) bootpd(1M) Dhcpdeny Configuration The configuration file /etc/dhcpdeny contains the list of hardware addresses, one address per line, for clients that will not be served by our server. If we know about some bad clients in the network and we don’t want to serve them, add the hardware address of those clients in this file. This file, like other configuration files, takes # character as the starting of a comment.
PAGE 8
bootpd(1M) bootpd(1M) callback-style=OLD |NEW Callbacks are a powerful feature that allow the system administrator to customize the operation of the server. A user-supplied executable file (typically a shell script) is executed each time one of the main server actions is performed (example: granting a lease). An argument list is passed in with information about the individual client and the lease.
PAGE 9
bootpd(1M) bootpd(1M) call-on-release=filename This tag specifies the fully qualified filename to be called when an IP address has been released by a client. Some arguments will be passed in, the call will be made as follows: filename : client-id htype haddr ipaddr lease-expiration where client-id is the client ID in hex if present, or 00 if there is no client ID. htype is the hardware type as per the ARP section of the "Assigned Numbers" RFC. haddr is the hardware address in hex.
PAGE 10
bootpd(1M) bootpd(1M) addr-pool-start-address=IP-address This tag specifies the lowest address in the pool group to be assigned. This tag is required for both dhcp_device_group and dhcp_pool_group, and is inappropriate for dhcp_default_client_settings. addr-pool-last-address=ip-address This tag specifies the highest address in the pool group to be assigned. This address and the addr-pool-start-address define a range of addresses that can be assigned to clients.
PAGE 11
bootpd(1M) bootpd(1M) DHCP/BOOTP Packet The DHCP/BOOTP packet has the following format: struct dhcp { unsigned char unsigned char unsigned char unsigned char unsigned long unsigned short unsigned short struct in_addr struct in_addr struct in_addr struct in_addr unsigned char unsigned char unsigned char unsigned char }; op; htype; hlen; hops; xid; secs; flags; ciaddr; yiaddr; siaddr; giaddr; chaddr[16]; sname[64]; file[128]; options[312]; /* /* /* /* /* /* /* /* /* /* /* /* /* /* /* packet opcode type
PAGE 12
bootpd(1M) 61 64 65 69 bootpd(1M) ci pd ps ms Client Identifier NIS+ Domain NIS+ Servers SMTP Servers EXAMPLES This is an example of a /etc/bootptab file: # Common entry A global.defaults:\ bf=C2300A:\ hd=/usr/lib/X11/:\ hn:\ ht=ether:\ vm=rfc1048 bA # Now the actual individual entries xterm1:\ tc=global.defaults:\ ha=08000903212F:\ ip=190.40.101.22 xterm2:\ tc=global.defaults:\ ha=0800090324AC:\ ip=190.40.101.35 # Common relay entry. relay-default:\ ht=ethernet:\ bp=15.4.3.136 15.13.6.
PAGE 13
bootpd(1M) bootpd(1M) This is an example of a /etc/dhcptab file: # The first entry is for options which define the server’s operation. DHCP_SERVER_SETTINGS:\ call-on-unrequited="/tmp/unrequited.script" :\ allow-subnet-selection :\ dhcpdb-write-perf= 3 :\ # The next entry is for options that will be applied to all groups. # Individual options may be overridden for a specific group if the group # also configures the option.
PAGE 14
bootpd(1M) bootpd(1M) AUTHOR bootpd was developed by Carnegie Mellon University, Stanford University, and HP. FILES /etc/bootptab /etc/dhcptab /etc/services SEE ALSO bootpquery(1M), dhcptools(1M), inetd(1M), tftpd(1M), syslog(3C), hosts(4). A DARPA Internet Requests For Comments: RFC865, RFC868, RFC887, RFC951, RFC1010, RFC1034, RFC1048, RFC1084, RFC1395, RFC1533, RFC1534, RFC1541, RFC1542, RFC2131, RFC2132, RFC3011.