nnaammeedd is a Domain Name System (DNS) server, part of the BIND 9 distribution from ISC. For more information on the DNS, see RFCs 1033, 1034, and 1035.
When invoked without arguments, nnaammeedd will read the default configuration file _/_e_t_c_/_n_a_m_e_d_._c_o_n_f, read any initial data, and listen for queries.
-4 Use IPv4 only even if the host machine is capable of IPv6. --44 and --66 are mutually exclusive.
-6 Use IPv6 only even if the host machine is capable of IPv4. --44 and --66 are mutually exclusive.
-c _c_o_n_f_i_g_-_f_i_l_e Use _c_o_n_f_i_g_-_f_i_l_e as the configuration file instead of the default, _/_e_t_c_/_n_a_m_e_d_._c_o_n_f. To ensure that reloading the configuration file continues to work after the server has changed its working directory due to to a possible ddiirreeccttoorryy option in the configuration file, _c_o_n_f_i_g_-_f_i_l_e should be an absolute pathname.
-d _d_e_b_u_g_-_l_e_v_e_l Set the daemon's debug level to _d_e_b_u_g_-_l_e_v_e_l. Debugging traces from nnaammeedd become more verbose as the debug level increases.
-f Run the server in the foreground (i.e. do not daemonize).
-g Run the server in the foreground and force all logging to _s_t_d_e_r_r.
-m _f_l_a_g Turn on memory usage debugging flags. Possible flags are _u_s_a_g_e, _t_r_a_c_e, _r_e_c_o_r_d, _s_i_z_e, and _m_c_t_x. These correspond to the ISC_MEM_DEBUGXXXX flags described in _<_i_s_c_/_m_e_m_._h_>.
-n _#_c_p_u_s Create _#_c_p_u_s worker threads to take advantage of multiple CPUs. If not specified, nnaammeedd will try to determine the number of CPUs present and create one thread per CPU. If it is unable to determine the number of CPUs, a single worker thread will be created.
-p _p_o_r_t Listen for queries on port _p_o_r_t. If not specified, the default is port 53.
-s Write memory usage statistics to _s_t_d_o_u_t on exit. Note: This option is mainly of interest to BIND 9 developers and may be removed or changed in a future release.
-S _#_m_a_x_-_s_o_c_k_s Allow nnaammeedd to use up to _#_m_a_x_-_s_o_c_k_s sockets. Warning: This option should be unnecessary for the vast majority of users. The use of this option could even be harmful because the specified value may exceed the limitation of the underlying system API. It is therefore set only when the default configuration causes exhaustion of file descriptors and the operational environment is known to support the specified number of sockets. Note also that the actual maximum number is normally a little fewer than the specified value because nnaammeedd reserves some file descriptors for its internal use.
-t _d_i_r_e_c_t_o_r_y Chroot to _d_i_r_e_c_t_o_r_y after processing the command line arguments, but before reading the configuration file. Warning: This option should be used in conjunction with the --uu option, as chrooting a process running as root doesn't enhance security on most systems; the way cchhrroooott((22)) is defined allows a process with root privileges to escape a chroot jail.
-u _u_s_e_r Setuid to _u_s_e_r after completing privileged operations, such as creating sockets that listen on privileged ports. Note: On Linux, nnaammeedd uses the kernel's capability mechanism to drop all root privileges except the ability to bbiinndd((22)) to a privileged port and set process resource limits. Unfortunately, this means that the --uu option only works when nnaammeedd is run on kernel 2.2.18 or later, or kernel 2.3.99-pre3 or later, since previous kernels did not allow privileges to be retained after sseettuuiidd((22)).
-v Report the version number and exit.
-x _c_a_c_h_e_-_f_i_l_e Load data from _c_a_c_h_e_-_f_i_l_e into the cache of the default view. Warning: This option must not be used. It is only of interest to BIND 9 developers and may be removed or changed in a future release.
In routine operation, signals should not be used to control the nameserver; rrnnddcc should be used instead.
SIGHUP Force a reload of the server.
SIGINT, SIGTERM Shut down the server.
The result of sending any other signals to the server is undefined.
The nnaammeedd configuration file is too complex to describe in detail here. A complete description is provided in the BIND 9 Administrator Reference Manual.
_/_e_t_c_/_n_a_m_e_d_._c_o_n_f The default configuration file.
_/_v_a_r_/_r_u_n_/_n_a_m_e_d_._p_i_d The default process-id file.
RFC 1033, RFC 1034, RFC 1035, nnaammeedd--cchheecckkccoonnff(8), nnaammeedd--cchheecckkzzoonnee(8), rrnnddcc(8), llwwrreessdd(8), nnaammeedd..ccoonnff(5), BIND 9 Administrator Reference Manual.
Internet Systems Consortium