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。

• ​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

• ​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

• ​setting the DNS search string

  option domain-search domain-list;

  This was added in 3.1.0.
  (snip)
  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).