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diff --git a/server/dhcpd.cat8 b/server/dhcpd.cat8 deleted file mode 100644 index d046e509..00000000 --- a/server/dhcpd.cat8 +++ /dev/null @@ -1,330 +0,0 @@ - - - -dhcpd(8) dhcpd(8) - - -NNAAMMEE - dhcpd - Dynamic Host Configuration Protocol Server - -SSYYNNOOPPSSIISS - ddhhccppdd [ --pp _p_o_r_t ] [ --ff ] [ --dd ] [ --ccff _c_o_n_f_i_g_-_f_i_l_e ] [ --llff - _l_e_a_s_e_-_f_i_l_e ] [ _i_f_0 [ _._._._i_f_N ] ] - -DDEESSCCRRIIPPTTIIOONN - The Internet Software Consortium DHCP Server, dhcpd, - implements the Dynamic Host Configuration Protocol (DHCP) - and the Internet Bootstrap Protocol (BOOTP). DHCP allows - hosts on a TCP/IP network to request and be assigned IP - addresses, and also to discover information about the net- - work to which they are attached. BOOTP provides similar - functionality, with certain restrictions. - -OOPPEERRAATTIIOONN - The DHCP protocol allows a host which is unknown to the - network administrator to be automatically assigned a new - IP address out of a pool of IP addresses for its network. - In order for this to work, the network administrator allo- - cates address pools in each subnet and enters them into - the dhcpd.conf(5) file. - - On startup, dhcpd reads the _d_h_c_p_d_._c_o_n_f file and stores a - list of available addresses on each subnet in memory. - When a client requests an address using the DHCP protocol, - dhcpd allocates an address for it. Each client is - assigned a lease, which expires after an amount of time - chosen by the administrator (by default, one day). Before - leases expire, the clients to which leases are assigned - are expected to renew them in order to continue to use the - addresses. Once a lease has expired, the client to which - that lease was assigned is no longer permitted to use the - leased IP address. - - In order to keep track of leases across system reboots and - server restarts, dhcpd keeps a list of leases it has - assigned in the dhcpd.leases(5) file. Before dhcpd - grants a lease to a host, it records the lease in this - file and makes sure that the contents of the file are - flushed to disk. This ensures that even in the event of - a system crash, dhcpd will not forget about a lease that - it has assigned. On startup, after reading the - dhcpd.conf file, dhcpd reads the dhcpd.leases file to - refresh its memory about what leases have been assigned. - - New leases are appended to the end of the dhcpd.leases - file. In order to prevent the file from becoming arbi- - trarily large, from time to time dhcpd creates a new - dhcpd.leases file from its in-core lease database. Once - this file has been written to disk, the old file is - renamed _d_h_c_p_d_._l_e_a_s_e_s_~, and the new file is renamed - dhcpd.leases. If the system crashes in the middle of - - - - 1 - - - - - -dhcpd(8) dhcpd(8) - - - this process, whichever dhcpd.leases file remains will - contain all the lease information, so there is no need for - a special crash recovery process. - - BOOTP support is also provided by this server. Unlike - DHCP, the BOOTP protocol does not provide a protocol for - recovering dynamically-assigned addresses once they are no - longer needed. It is still possible to dynamically - assign addresses to BOOTP clients, but some administrative - process for reclaiming addresses is required. By - default, leases are granted to BOOTP clients in perpetu- - ity, although the network administrator may set an earlier - cutoff date or a shorter lease length for BOOTP leases if - that makes sense. - - BOOTP clients may also be served in the old standard way, - which is to simply provide a declaration in the dhcpd.conf - file for each BOOTP client, permanently assigning an - address to each client. - - Whenever changes are made to the dhcpd.conf file, dhcpd - must be restarted. To restart dhcpd, send a SIGTERM - (signal 15) to the process ID contained in - _/_v_a_r_/_r_u_n_/_d_h_c_p_d_._p_i_d, and then re-invoke dhcpd. Because the - DHCP server database is not as lightweight as a BOOTP - database, dhcpd does not automatically restart itself when - it sees a change to the dhcpd.conf file. - -CCOOMMMMAANNDD LLIINNEE - The names of the network interfaces on which dhcpd should - listen for broadcasts may be specified on the command - line. This should be done on systems where dhcpd is - unable to identify non-broadcast interfaces, but should - not be required on other systems. If no interface names - are specified on the command line dhcpd will identify all - network interfaces which are up, elimininating non- - broadcast interfaces if possible, and listen for DHCP - broadcasts on each interface. - - If dhcpd should listen on a port other than the standard - (port 67), the --pp flag may used. It should be followed by - the udp port number on which dhcpd should listen. This is - mostly useful for debugging purposes. - - To run dhcpd as a foreground process, rather than allowing - it to run as a daemon in the background, the --ff flag - should be specified. This is useful when running dhcpd - under a debugger, or when running it out of inittab on - System V systems. - - To have dhcpd log to the standard error descriptor, spec- - ify the --dd flag. This can be useful for debugging, and - also at sites where a complete log of all dhcp activity - must be kept but syslogd is not reliable or otherwise - - - - 2 - - - - - -dhcpd(8) dhcpd(8) - - - cannot be used. Normally, dhcpd will log all output - using the syslog(3) function with the log facility set to - LOG_DAEMON. - - Dhcpd can be made to use an alternate configuration file - with the --ccff flag, or an alternate lease file with the --llff - flag. Because of the importance of using the same lease - database at all times when running dhcpd in production, - these options should be used oonnllyy for testing lease files - or database files in a non-production environment. - -CCOONNFFIIGGUURRAATTIIOONN - The syntax of the dhcpd.conf(8) file is discussed seper- - ately. This section should be used as an overview of the - configuration process, and the dhcpd.conf(8) documentation - should be consulted for detailed reference information. - - -SSuubbnneettss - dhcpd needs to know the subnet numbers and netmasks of all - subnets for which it will be providing service. In addi- - tion, in order to dynamically allocate addresses, it must - be assigned one or more ranges of addresses on each subnet - which it can in turn assign to client hosts as they boot. - Thus, a very simple configuration providing DHCP support - might look like this: - - subnet 239.252.197.0 netmask 255.255.255.0 { - range 239.252.197.10 239.252.197.250; - } - - Multiple address ranges may be specified like this: - - subnet 239.252.197.0 netmask 255.255.255.0 { - range 239.252.197.10 239.252.197.107; - range 239.252.197.113 239.252.197.250; - } - - If a subnet will only be provided with BOOTP service and - no dynamic address assignment, the range clause can be - left out entirely, but the subnet statement must appear. - - -LLeeaassee LLeennggtthhss - DHCP leases can be assigned almost any length from zero - seconds to infinity. What lease length makes sense for - any given subnet, or for any given installation, will vary - depending on the kinds of hosts being served. - - For example, in an office environment where systems are - added from time to time and removed from time to time, but - move relatively infrequently, it might make sense to allow - lease times of a month of more. In a final test environ- - ment on a manufacturing floor, it may make more sense to - - - - 3 - - - - - -dhcpd(8) dhcpd(8) - - - assign a maximum lease length of 30 minutes - enough time - to go through a simple test procedure on a network appli- - ance before packaging it up for delivery. - - It is possible to specify two lease lengths: the default - length that will be assigned if a client doesn't ask for - any particular lease length, and a maximum lease length. - These are specified as clauses to the subnet command: - - subnet 239.252.197.0 netmask 255.255.255.0 { - range 239.252.197.10 239.252.197.107; - default-lease-time 600; - max-lease-time 7200; - | - - This particular subnet declaration specifies a default - lease time of 600 seconds (ten minutes), and a maximum - lease time of 7200 seconds (two hours). Other common - values would be 86400 (one day), 604800 (one week) and - 2592000 (30 days). - - Each subnet need not have the same lease--in the case of - an office environment and a manufacturing environment - served by the same DHCP server, it might make sense to - have widely disparate values for default and maximum lease - times on each subnet. - -BBOOOOTTPP SSuuppppoorrtt - Each BOOTP client must be explicitly declared in the - dhcpd.conf file. A very basic client declaration will - specify the client network interface's hardware address - and the IP address to assign to that client. If the - client needs to be able to load a boot file from the - server, that file's name must be specified. A simple - bootp client declaration might look like this: - - host haagen { - hardware ethernet 08:00:2b:4c:59:23; - fixed-address 239.252.197.9; - filename "/tftpboot/haagen.boot"; - } - -OOppttiioonnss - DHCP (and also BOOTP with Vendor Extensions) provide a - mechanism whereby the server can provide the client with - information about how to configure its network interface - (e.g., subnet mask), and also how the client can access - various network services (e.g., DNS, IP routers, and so - on). - - These options can be specified on a per-subnet basis, and, - for BOOTP clients, also on a per-client basis. In the - event that a BOOTP client declaration specifies options - that are also specified in its subnet declaration, the - - - - 4 - - - - - -dhcpd(8) dhcpd(8) - - - options specified in the client declaration take prece- - dence. An reasonably complete DHCP configuration might - look something like this: - - subnet 239.252.197.0 netmask 255.255.255.0 { - range 239.252.197.10 239.252.197.250; - default-lease-time 600 max-lease-time 7200; - option subnet-mask 255.255.255.0; - option broadcast-address 239.252.197.255; - option routers 239.252.197.1; - option domain-name-servers 239.252.197.2, 239.252.197.3; - option domain-name "isc.org"; - } - - A bootp host on that subnet that needs to be in a differ- - ent domain and use a different name server might be - declared as follows: - - host haagen hardware ethernet 08:00:2b:4c:59:23 { - fixed-address 239.252.197.9; - filename "/tftpboot/haagen.boot"; - option domain-name-servers 192.5.5.1; - option domain-name "vix.com"; - } - - A more complete description of the dhcpd.conf file syntax - is provided in dhcpd.conf(5). - -FFIILLEESS - //eettcc//ddhhccppdd..ccoonnff,, //vvaarr//ddbb//ddhhccppdd..lleeaasseess,, //vvaarr//rruunn//ddhhccppdd..ppiidd,, - //vvaarr//ddbb//ddhhccppdd..lleeaasseess~~.. - -SSEEEE AALLSSOO - dhcpd.conf(5), dhcpd.leases(5) - -AAUUTTHHOORR - ddhhccppdd((88)) was written by Ted Lemon <mellon@vix.com> under a - contract with Vixie Labs. Funding for this project was - provided by the Internet Software Corporation. Informa- - tion about the Internet Software Consortium can be found - at hhttttpp::////wwwwww..iisscc..oorrgg//iisscc.. - - - - - - - - - - - - - - - - - 5 - - |