NLSADMIN(8) Maintenance Commands and Procedures NLSADMIN(8)

NAME

nlsadmin - network listener service administration

SYNOPSIS

/usr/sbin/nlsadmin -x


/usr/sbin/nlsadmin [options] net_spec


/usr/sbin/nlsadmin [options] -N port_monitor_tag


/usr/sbin/nlsadmin -V


/usr/sbin/nlsadmin -c cmd | -o streamname [-p modules]
[-A address | -D] [-R prognum : versnum]

DESCRIPTION

nlsadmin is the administrative command for the network listener
process(es) on a machine. Each network has at least one instance of
the network listener process associated with it; each instance (and
thus, each network) is configured separately. The listener process
``listens'' to the network for service requests, accepts requests
when they arrive, and invokes servers in response to those service
requests. The network listener process may be used with any network
(more precisely, with any connection-oriented transport provider)
that conforms to the transport provider specification.


nlsadmin can establish a listener process for a given network,
configure the specific attributes of that listener, and start and
kill the listener process for that network. nlsadmin can also report
on the listener processes on a machine, either individually (per
network) or collectively.


net_spec represents a particular listener process. Specifically,
net_spec is the relative path name of the entry under /dev for a
given network (that is, a transport provider). address is a transport
address on which to listen and is interpreted using a syntax that
allows for a variety of address formats. By default, address is
interpreted as the symbolic ASCII representation of the transport
address. An address preceded by \x will let you enter an address in
hexadecimal notation. Note that address must appear as a single word
to the shell, thus it must be quoted if it contains any blanks.


Changes to the list of services provided by the listener or the
addresses of those services are put into effect immediately.

OPTIONS

nlsadmin may be used with the following combinations of options and
arguments:

-x

Report the status of all of the listener processes installed on
this machine.


net_spec

Print the status of the listener process for net_spec .


-q net_spec

Query the status of the listener process for the specified
network, and reflects the result of that query in its exit code.
If a listener process is active, nlsadmin will exit with a status
of 0; if no process is active, the exit code will be 1; the exit
code will be greater than 1 in case of error.


-v net_spec

Print a verbose report on the servers associated with net_spec,
giving the service code, status, command, and comment for each.
It also specifies the uid the server will run as and the list of
modules to be pushed, if any, before the server is started.


-z service_code net_spec

Print a report on the server associated with net_spec that has
service code service_code, giving the same information as in the
-v option.


-q -z service_code net_spec

Query the status of the service with service code service_code on
network net_spec, and exits with a status of 0 if that service is
enabled, 1 if that service is disabled, and greater than 1 in
case of error.


-l address net_spec

Change or set the transport address on which the listener listens
(the general listener service). This address can be used by
remote processes to access the servers available through this
listener (see the -a option, below).

If address is just a dash (" - "), nlsadmin reports the address
currently configured, instead of changing it.

A change of address takes effect immediately.


-t address net_spec

Change or set the address on which the listener listens for
requests for terminal service but is otherwise similar to the -l
option above. A terminal service address should not be defined
unless the appropriate remote login software is available; if
such software is available, it must be configured as service code
1 (see the -a option, below).


-i net_spec

Initialize an instance of the listener for the network specified
by net_spec; that is, create and initialize the files required by
the listener as well as starting that instance of the listener.
Note that a particular instance of the listener should be
initialized only once. The listener must be initialized before
assigning addresses or services.


-a service_code

[ -p modules ] [ -w name ] -c cmd -y comment net_spec

Add a new service to the list of services available through the
indicated listener. service_code is the code for the service, cmd
is the command to be invoked in response to that service code,
comprised of the full path name of the server and its arguments,
and comment is a brief (free-form) description of the service for
use in various reports. Note that cmd must appear as a single
word to the shell; if arguments are required, the cmd and its
arguments must be enclosed in quotation marks. The comment must
also appear as a single word to the shell. When a service is
added, it is initially enabled (see the -e and -d options,
below).

Service codes are alphanumeric strings, and are administered by
AT&T. The numeric service codes 0 through 100 are reserved for
internal use by the listener. Service code 0 is assigned to the
nlps server, which is the service invoked on the general
listening address. In particular, code 1 is assigned to the
remote login service, which is the service automatically invoked
for connections to the terminal login address.

If the -p option is specified, then modules will be interpreted
as a list of STREAMS modules for the listener to push before
starting the service being added. The modules are pushed in the
order they are specified. modules should be a comma-separated
list of modules, with no white space included.

If the -w option is specified, then name is interpreted as the
user name from /etc/passwd that the listener should look up. From
the user name, the listener obtains the user ID, the group ID(s),
and the home directory for use by the server. If -w is not
specified, the default is to use the user name listen.

A service must explicitly be added to the listener for each
network on which that service is to be available. This operation
will normally be performed only when the service is installed on
a machine, or when populating the list of services for a new
network.


-r service_code net_spec

Remove the entry for the service_code from that listener's list
of services. This is normally done only in conjunction with the
de-installation of a service from a machine.


-e service_code net_spec
-d service_code net_spec

Enable or disable (respectively) the service indicated by
service_code for the specified network. The service must
previously have been added to the listener for that network (see
the -a option, above). Disabling a service will cause subsequent
service requests for that service to be denied, but the processes
from any prior service requests that are still running will
continue unaffected.


-s net_spec
-k net_spec

Start and kill (respectively) the listener process for the
indicated network. These operations are normally performed as
part of the system startup and shutdown procedures. Before a
listener can be started for a particular network, it must first
have been initialized (see the -i option, above). When a listener
is killed, processes that are still running as a result of prior
service requests will continue unaffected.


Under the Service Access Facility, it is possible to have multiple
instances of the listener on a single net_spec. In any of the above
commands, the option -N port_monitor_tag may be used in place of the
net_spec argument. This argument specifies the tag by which an
instance of the listener is identified by the Service Access
Facility. If the -N option is not specified (that is, the net_spec is
specified in the invocation), then it will be assumed that the last
component of the net_spec represents the tag of the listener for
which the operation is destined. In other words, it is assumed that
there is at least one listener on a designated net_spec, and that its
tag is identical to the last component of the net_spec. This listener
may be thought of as the primary, or default, listener for a
particular net_spec.


nlsadmin is also used in conjunction with the Service Access Facility
commands. In that capacity, the following combinations of options can
be used:

-V

Write the current version number of the listener's administrative
file to the standard output. It is used as part of the sacadm
command line when sacadm adds a port monitor to the system.


-c cmd | -o streamname [ -p modules ] [ -A address | -D ] [ -R
prognum : versnum ]

Format the port monitor-specific information to be used as an
argument to pmadm(8)

The -c option specifies the full path name of the server and its
arguments. cmd must appear as a single word to the shell, and its
arguments must therefore be surrounded by quotes.

The -o option specifies the full path name of a FIFO or named
stream through which a standing server is actually receiving the
connection.

If the -p option is specified, then modules will be interpreted
as a list of STREAMS modules for the listener to push before
starting the service being added. The modules are pushed in the
order in which they are specified. modules must be a comma-
separated list, with no white space included.

If the -A option is specified, then address will be interpreted
as the server's private address. The listener will monitor this
address on behalf of the service and will dispatch all calls
arriving on this address directly to the designated service. This
option may not be used in conjunction with the -D option.

If the -D option is specified, then the service is assigned a
private address dynamically, that is, the listener will have the
transport provider select the address each time the listener
begins listening on behalf of this service. For RPC services,
this option will be often be used in conjunction with the -R
option to register the dynamically assigned address with the
rpcbinder. This option may not be used in conjunction with the -A
option.

When the -R option is specified, the service is an RPC service
whose address, program number, and version number should be
registered with the rpcbinder for this transport provider. This
registration is performed each time the listener begins listening
on behalf of the service. prognum and versnum are the program
number and version number, respectively, of the RPC service.


nlsadmin may be invoked by any user to generate reports; all
operations that affect a listener's status or configuration may only
be run by a super-user.


The options specific to the Service Access Facility may not be used
together with any other options.

ERRORS

If successful, nlsadmin exits with a status of 0. If nlsadmin
fails for any reason, it exits with a status greater than or equal to
2. See -q option for a return status of 1.

SEE ALSO

attributes(7), listen(8), pmadm(8), rpcbind(8), sacadm(8)

NOTES

Dynamically assigned addresses are not displayed in reports as
statically assigned addresses are.

April 3, 1997 NLSADMIN(8)