telnet-probe(1) — Linux manual page


TELNET-PROBE(1)          General Commands Manual         TELNET-PROBE(1)

NAME         top

       telnet-probe - lightweight telnet-like port probe

SYNOPSIS         top

       $PCP_BINADM_DIR/telnet-probe [-cv?]  host port

DESCRIPTION         top

       telnet-probe allows the pmdashping(1) daemons to establish
       connections to arbitrary local and remote service-providing
       daemons so that response time and service availability
       information can be obtained.

       The required host and port number arguments have the same meaning
       as their telnet(1) equivalents.

       The -c option causes telnet-probe to perform a connect(2) only.
       This skips the read(2) and write(2) exercise that would otherwise
       be done after connecting (see below).

       Once the telnet connection has been established, telnet-probe
       reads from stdin until end-of-file, and writes all the input data
       to the telnet connection.  Next, telnet-probe will read from the
       telnet connection until end-of-file, discarding whatever data it
       receives.  Then telnet-probe exits.

       To operate successfully, the input passed via telnet-probe to the
       remote service must be sufficient to cause the remote service to
       close the connection when the last line of input has been
       processed, e.g. ending with ``quit'' when probing SMTP on port

       By default telnet-probe will not produce any output, unless there
       is an error in which case a diagnostic message can be displayed
       (in verbose mode only) and the exit status will be non-zero
       indicating a failure.

OPTIONS         top

       The available command line options are:

       -c   Connect only, do not read or write.

       -v   Enable verbose mode.

       -?   Display usage message and exit.

DIAGNOSTICS         top

       If telnet-probe succeeds, then 0 will be returned.  If the
       attempt to establish a connection fails or is terminated, then a
       non-zero exit status is returned.


       Environment variables with the prefix PCP_ are used to
       parameterize the file and directory names used by PCP.  On each
       installation, the file /etc/pcp.conf contains the local values
       for these variables.  The $PCP_CONF variable may be used to
       specify an alternative configuration file, as described in

SEE ALSO         top

       PCPIntro(1), pmdashping(1), pmie(1), telnet(1), connect(2),
       read(2) and write(2).

COLOPHON         top

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Performance Co-Pilot               PCP                   TELNET-PROBE(1)