{"id":7,"date":"2011-03-26T02:15:06","date_gmt":"2011-03-26T01:15:06","guid":{"rendered":"http:\/\/www.dhcp.net\/?page_id=7"},"modified":"2014-08-25T14:32:05","modified_gmt":"2014-08-25T13:32:05","slug":"isc-dhcp-server","status":"publish","type":"page","link":"https:\/\/www.dhcp.net\/?page_id=7","title":{"rendered":"DHCPv4 HOWTO (ISC-DHCP)"},"content":{"rendered":"

The Internet Software Consortium’s<\/a> DHCP daemon software<\/a> is perhaps the most well-known implementation available. Free as in beer, it comes standard or can be installed on most Linux distributions.<\/p>\n

The dhclient<\/a> is the client suite of the Internet Software Consortiums’s<\/a> DHCP server<\/a> software. It is normally installed alongside its server counterpart, dhcpd<\/a>.<\/p>\n

Configuration is in readable text:<\/p>\n

# Configuration file for \/sbin\/dhclient, which is included in Debian's
\n# dhcp3-client package.
\noption rfc3442-classless-static-routes code 121 = array of unsigned integer 8;
\nsend host-name \"\";
\n#send dhcp-client-identifier 1:0:a0:24:ab:fb:9c;
\n#send dhcp-lease-time 3600;
\n#supersede domain-name \"fugue.com home.vix.com\";
\n#prepend domain-name-servers 127.0.0.1;
\nrequest subnet-mask, broadcast-address, time-offset, routers,
\ndomain-name, domain-name-servers, domain-search, host-name,
\nnetbios-name-servers, netbios-scope, interface-mtu,
\nrfc3442-classless-static-routes, ntp-servers;
\n#require subnet-mask, domain-name-servers;
\n#timeout 60;
\n#retry 60;
\n#reboot 10;
\n#select-timeout 5;
\n#initial-interval 2;
\n#script \"\/etc\/dhcp3\/dhclient-script\";
\n#media \"-link0 -link1 -link2\", \"link0 link1\";
\n#reject 192.33.137.209;
\n#alias {
\n# interface \"eth0\";
\n# fixed-address 192.5.5.213;
\n# option subnet-mask 255.255.255.255;
\n#}<\/code><\/p>\n

DHCP Server configuration is done in a nested fashion, by declaring subnets, settings and hosts in that subnet, for example:<\/p>\n

ddns-update-style none; \/\/ Do not update Dynamic DNS entries
\nauthoritative; \/\/ Declares this DHCP server to be the primary one on this network
\nping-check true; \/\/ Check if an IP is in use before giving it out
\nsubnet 192.168.0.0 netmask 255.255.255.0 { \/\/ What subnet are we using?
\ndeny unknown-clients; \/\/ Do not allow unknown machines on the network
\nrange 192.168.0.100 192.168.0.150; \/\/ Serve addresses from this range
\noption domain-name-servers 4.4.4.4, 8.8.8.8; \/\/ The DNS-servers
\noption ntp-servers time.nasa.gov; \/\/ Specifies the NTP-server in use
\noption domain-name \"dhcp.net\";
\noption routers 192.168.0.254;
\noption broadcast-address 192.168.0.255;
\nnext-server 192.168.0.200; \/\/ Used for TFTP\/PXE\/netbooting
\nfilename \"pxelinux.0\"; \/\/ File loaded from the TFTP server
\ndefault-lease-time 86400; \/\/ By default, give out addresses for 24 hours
\nmax-lease-time 86400; \/\/ Do not allow clients use addresses for more than 24 hours
\nhost staticserver { \/\/ Give the machine this hostname
\nhardware ethernet 00:1f:d3:6e:3a:7c; \/\/ This MAC address...
\nfixed-address 192.168.0.180; \/\/ ...is offered this IP
\n}
\n}<\/code><\/p>\n","protected":false},"excerpt":{"rendered":"

The Internet Software Consortium’s DHCP daemon software is perhaps the most well-known implementation available. Free as in beer, it comes standard or can be installed on most Linux distributions. The dhclient is the client suite of the Internet Software Consortiums’s … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":2,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-7","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.dhcp.net\/index.php?rest_route=\/wp\/v2\/pages\/7","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.dhcp.net\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.dhcp.net\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.dhcp.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.dhcp.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=7"}],"version-history":[{"count":6,"href":"https:\/\/www.dhcp.net\/index.php?rest_route=\/wp\/v2\/pages\/7\/revisions"}],"predecessor-version":[{"id":147,"href":"https:\/\/www.dhcp.net\/index.php?rest_route=\/wp\/v2\/pages\/7\/revisions\/147"}],"wp:attachment":[{"href":"https:\/\/www.dhcp.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=7"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}