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dhcpcemu(8) [osf1 man page]

dhcpcemu(8)						      System Manager's Manual						       dhcpcemu(8)

NAME

       dhcpcemu - Emulate a DHCP client

SYNOPSIS

       /usr/sbin/dhcpcemu  [-b]  [-q]  [-m   |	-n   |	-v]  [-dn] [-a server_address] [-c client_address] [-e hardware_address] [-h hostname] [-i
       client_identifier] [-r requested_address] [-p bootp | discover | renew | rebind | request | select | decline] [-s size]	[-t  timeout]  [-f
       file] interface

OPTIONS

       Sets the broadcast bit.	Runs quietly: display neither the contents of the incoming nor the outgoing packets.  Sets the magic cookie in the
       outgoing packet to be the CMU (-m) or the RFC1048 (-v ) value (the default).  The -n option means to use no  cookie  at	all.   The  server
       identifier field in the options of the outgoing packet is set to the IP address.  To properly emulate a client in the selecting DHCP state,
       this field is required regardless of the value given with the -p option.  Sets the ciaddr field in the packet to the  value  client_address
       or  to  the  IP	address  of the interface chosen if client_address equals 0.0.0.0.  Pretend to be at the given hardware (MAC) address. The
       chaddr field is set to hardware_address.  Unless the broadcast bit is also set, this usually means that no replies will be received, as the
       server or relay agents will normally try a link-level unicast to the phony address.  Sets the hostname option in the outgoing packet to the
       given value.  Sets the client identifier option in the outgoing packet to the given string. The string is treated literally, not as  a  hex
       representation  of  an  arbitrary  octet string.  Sets the IP address value in the outgoing packet. This option is required if the outgoing
       packet is to validly represent a client in the DHCP states selecting or rebooting or in a  DHCP	DECLINE  message.   The  string  following
       determines  the	kind  of  BOOTP  or  DHCP  packet sent, and whether the packet is broadcast or unicast.  The default is to emulate a BOOTP
       client.	Sends a packet of size octets (by default 548 octets).	Exits after timeout seconds if no responses are received.  Sets  the  file
       field in the outgoing packet to the given string.

DESCRIPTION

       The  dhcpcemu  command emulates a DHCP/BOOTP client.  Options are provided to set the most important fields in the BOOTP request packet.  A
       packet is constructed, is sent through the interface specified, and a reply awaited. The emulator exits after the first reply  is  received
       or  for	a length of time specified by the -t option. Depending on the options specified and/or the DHCP server configuration, no reply may
       in fact be forthcoming. If no timeout is specified, the emulator may be killed with any suitable asynchronous signal.   The  SIGINT  signal
       (usually generated from the keyboard with Ctrl/c) is available if dhcpcemu is running in the foreground.

       It is important to note that with the options available, it is quite possible to create an illegal packet. This is one of the primary func-
       tions of dhcpcemu; to test the behavior of servers when confronted with packets that do not conform to the standards.

RESTRICTIONS

       A cluster member should never be a DHCP client. It should always use static addressing.

       If a cluster is to support a DHCP server, there can be only one DHCP server for all the	cluster  members  using  a  common  database  with
       failover.

SEE ALSO

       RFC2031, RFC2032

																       dhcpcemu(8)

Check Out this Related Man Page

dhcpparm(8)						      System Manager's Manual						       dhcpparm(8)

NAME

       dhcpparm - Daemon for client configuration

SYNOPSIS

       /usr/sbin/dhcpparm [-i interface] tag | symbol | name

OPTIONS

       Use  this  option  on  hardware	that  has two or more interfaces configurable by the Dynamic Host Configuration Protocol (DHCP), and for a
       parameter that is interface specific. When no interface is specified, the client daemon returns the name of the first interface it finds on
       which DHCP has successfully completed: the value(s) displayed will be those of the configuration received on that interface.

DESCRIPTION

       The  dhcpparm  command  displays the value(s) of the parameter requested on the command line as supplied by the DHCP protocol.  If the DHCP
       parameter implies more than one value (for example, a list of gateways), the values are displayed  separated  by  newline  characters.  The
       parameter  may  be identified either by its numeric value in the DHCP protocol, by its two character symbol, or by its long name. The dhcp-
       parm command is intended to be used in command substitutions in the shell scripts invoked by init at system boot.  It  first  contacts  the
       DHCP  client daemon (joinc) to verify that DHCP has successfully completed. When the -i option specifies a particular interface, the daemon
       verifies successful DHCP configuration of that interface; otherwise, the client verifies that at least one interface is	successfully  con-
       figured, and supplies the name of that interface to dhcpparm.  Parameter values echoed by dhcpparm should not be used without checking exit
       status. See the EXIT STATUS section below.

RESTRICTIONS

       A cluster member should never be a DHCP client; it should always use static addressing.

       If a cluster is to support a DHCP server, there can only be one DHCP server for all the	cluster  members  using  a  common  database  with
       failover.

       If  a  cluster  is  to  support	a  DHCP server, there can only be one DHCP server for all the cluster members using a common database with
       failover.

       DHCP client is not supported on dataless clients.

SYMBOLS

       See dhcptags(4) for the list of two letter symbol codes and names of all DHCP parameters. See RFC 1533 for more detail.

EXIT STATUS

       Exit codes are as follows: Success.  DHCP was not successful. The DHCP client daemon may not be running, the interface might have failed to
       configure, or no satisfactory DHCP responses were received.  Bad arguments.  A timer was set and the interface had not configured before it
       expired.  Can only be run as root.  Some system error (should never occur).

SEE ALSO

       Commands: dhcpconf(8), joinc(8), showdhc(8), shleases(8)

       Files: client.pcy(4), dhcptags(4)

       RFC1533

																       dhcpparm(8)
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