[[PageOutline]]

 = DHCPd =
 * 標準はISC DHCPd
 * Ubuntuでは「udhcpd」という組み込み機器向け由来のDHCPdも選択できる。

 * [http://www.linux.or.jp/JM/html/dhcp2/man5/dhcpd.conf.5.html Manpage of dhcpd.conf]

 == logging ==
 * log-facility でsyslogへのログ出力を変更できる
 * Ubuntu:/etc/dhcp3/dhcpd.conf
{{{
# Use this to send dhcp log messages to a different log file (you also
# have to hack syslog.conf to complete the redirection).
log-facility local7;
}}}
 * syslog.conf
{{{
local7.* -/var/log/dhcpd.log
}}}

 * CentOSでは、local7はデフォルトでbootログ用に使われているようなので、変えた方が良いかもしれない。
   * /etc/syslog.conf
{{{
# Save boot messages also to boot.log
local7.*                                                /var/log/boot.log
}}}
   * /var/log/boot.log
{{{
Jul  1 16:43:03 VM-centos5 NET[3471]: /sbin/dhclient-script : updated /etc/resolv.conf
Jul  1 16:43:08 VM-centos5 NET[3562]: /sbin/dhclient-script : updated /etc/resolv.conf
Jul  1 16:47:13 VM-centos5 NET[3692]: /sbin/dhclient-script : updated /etc/resolv.conf
(snip)
}}}

 = Ubuntu =
 * aptitude install dhcp3-server
   * clientは標準ではdhcp3-client

 == configure ==
 * /etc/default/dhcp3-server
{{{
# On what interfaces should the DHCP server (dhcpd) serve DHCP requests?
#       Separate multiple interfaces with spaces, e.g. "eth0 eth1".
INTERFACES=""
}}}
   * ListenするIFを指定
 * /etc/dhcp3/dhcpd.conf についてはman dhcpd.conf

 == warning with dhcp3 ==
 * [https://bugs.launchpad.net/ubuntu/+source/dhcp3/+bug/39249 Bug #39249 in dhcp3 (Ubuntu): “(Dapper, Hardy) can't create /var/lib/dhcp3/dhclient.eth0.leases: Permission denied”]
  * sudo chown dhcp:dhcp /var/lib/dhcp3/

 = CentOS =
 * yum install dhcp
   * clientは標準ではdhclient

 == configure ==
 * /etc/sysconfig/dhcpd
{{{
# Command line options here
DHCPDARGS=
}}}
 * /etc/dhcpd.conf についてはman dhcpd.conf

 = searching multiple domains =
 * [https://lists.isc.org/pipermail/dhcp-users/2009-March/008326.html setting the DNS search string]
 > >   option domain-search domain-list;
 > This was added in 3.1.0.
 > [[br]](snip)[[br]]
 > You can configure 'option domain-name "example.com sales.example.com";',
 > and on many Unixish systems, this will become a 'search' string in
 > /etc/resolv.conf.  But it doesn't work as expected on many non-unixish
 > systems (they parse the spaces as part of the domain name).