On 2021-02-25, Werner Flamme <werner.fla...@ufz.de> wrote: > Am 2021-02-24 um 10:57 schrieb Piotr Kilar: >> Hello, >> I'm using Your check_tcp plugin and i'm need to monitor stunnel, but go= > t >> one issue. >> When stunnel certificates are expired or remote host is rejecting my >> connection check_tcp is showing me OK - port is open, and it is true >> because there is open local tcp port binded by stunnel process. But whe= > n >> using f.e. telnet i can see that "Connection closed by remote host" and= > see >> why in stunnel logs. Is it possible to adapt check_tcp to show CRIT in = > that >> cases (immediate port closure by remote host)? > > Hi Piotr, > > check_tcp does exactly what its name says: it checks a tcp port. Since > the port is open, the result is OK. > > If you want to check on an SSL certificate, you should use other > plugins, like check_ssl_cert. Or try to initiate some traffic over the > port, whatever software is at the back end of the stunnel (like, mail, > web server, ...).
Use check_tcp with -S and -D options, see the help text (check_tcp -h).
