NAME

inetd.conf - Internet servers database DESCRIPTION

Upon execution, inetd reads its configuration information from a configuration file which, by default, is /etc/inetd.conf. There must be an entry for each field of the configuration file, with entries for each field sepa- rated by a tab or a space. Comments are denoted by a ``#'' at the beginning of a line. There must be an entry for each field. The fields of the configuration file are as follows:

service name socket type protocol wait/nowait[.max? user[.group? server program server program arguments To specify an Sun-RPC based service, the entry would contain these fields.

service name/version socket type rpc/protocol wait/nowait[.max? user[.group? server program server program arguments The service-name entry is the name of a valid service in the file /etc/services. For ``internal services (discussed below), the service name must be the official name of the service (that is, the first entry in /etc/services). When used to specify a Sun-RPC based service, this field is a valid RPC service name in the file /etc/rpc. The part on the right of the ``/ is the RPC version number. This can simply be a single numeric argument or a range of versions. A range is bounded by the low version to the high version - ``rusers/1-3''.

The socket-type should be one of ``stream, ``dgram, ``raw, ``rdm, or ``seqpacket'', depending on whether the socket is a stream, datagram, raw, reliably delivered mes- sage, or sequenced packet socket.

The protocol must be a valid protocol as given in /etc/protocols. Examples might be ``tcp or ``udp. Rpc based services are specified with the ``rpc/tcp or ``rpc/udp service type.

The wait/nowait entry is applicable to datagram sockets only (other sockets should have a ``nowait entry in this space). If a datagram server connects to its peer, freeing the socket so inetd can received further messages on the socket, it is said to be a ``multi-threaded server, and should use the ``nowait entry. For datagram servers which process all incoming datagrams on a socket and eventually time out, the server is said to be ``single-threaded and should use a ``wait entry. comsat(8) (biff(1)) and talkd(8)? are both examples of the latter type of datagram server. tftpd(8)? is an exception; it is a datagram server that establishes pseudo-connections. It must be listed as ``wait in order to avoid a race; the server reads the first packet, creates a new socket, and then forks and exits to allow inetd to check for new service requests to spawn new servers. The optional ``max suffix (separated from ``wait or ``nowait by a dot) specifies the maximum num- ber of server instances that may be spawned from inetd within an interval of 60 seconds. When omitted, ``max defaults to 40.

The user entry should contain the user name of the user as whom the server should run. This allows for servers to be given less permission than root. An optional group name can be specified by appending a dot to the user name followed by the group name. This allows for servers to run with a dif- ferent (primary) group id than specified in the password file. If a group is specified and user is not root, the sup- plementary groups associated with that user will still be set.

The server-program entry should contain the pathname of the program which is to be executed by inetd when a request is found on its socket. If inetd provides this service inter- nally, this entry should be ``internal''.

The server program arguments should be just as arguments normally are, starting with argv[0?, which is the name of the program. If the service is provided internally, the word ``internal'' should take the place of this entry.

Inetd provides several ``trivial services internally by use of routines within itself. These services are ``echo, ``discard, ``chargen (character generator), ``daytime (human readable time), and ``time (machine readable time, in the form of the number of seconds since midnight, January 1, 1900). All of these services are tcp based. For details of these services, consult the appropriate RFC from the Net- work Information Center. BUGS

Lines in inetd.conf are limited to a maximum length of 1022 characters. SEE ALSO

inetd(8)

Linux !NetKit? 0.10 November 23, 1996 1