NAME¶
telnet-probe - lightweight telnet-like port probe
SYNOPSIS¶
$PCP_BINADM_DIR/telnet-probe [
-c] [
-v]
host
port
DESCRIPTION¶
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).
The
-v option causes
telnet-probe to be verbose while operating.
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 25.
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.
PCP ENVIRONMENT¶
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
pcp.conf(5).
DIAGNOSTICS¶
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.
SEE ALSO¶
PCPintro(1),
pmdashping(1),
pmie(1),
telnet(1),
connect(2),
read(2) and
write(2).