Monitoring TCP Ports

We have several Squid servers, some of which can be a bit unstable. However, they don't go down, they just stop listening on port 3128. Orion doesn't do anything, because he's still able to ping them. Is Orion able to monitor this?

If not, does anyone know how to do it with a shell script? I know it can be done, because a port scan will tell me if there's no response on port 3128. I just don't know how to do it from the shell.

Thanks,

Ron

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Accepted answers

rrichardson

Well, I figured out how to do it with a shell script. Works pretty nicely. If anyone would like a copy of the script, I'd be happy to send it to you.

All comments

Yann

Hi,

Application Performance Monitor can do this out of the box. You might want to give it a try.

Thanks,

Yann

rrichardson

Well, I figured out how to do it with a shell script. Works pretty nicely. If anyone would like a copy of the script, I'd be happy to send it to you.

Yann

Hi,

Please feel free to post the script in this thread (you can attach files to your post), I will be interested to see how you achieved it.

How do you notify Orion when the Port is down? Do you send a Syslog message or a SNMP Trap to Orion?

Thanks in advance for the details.

Yann

ElisabethZakes

Please feel free to post the script in this thread (you can attach files to your post), I will be interested to see how you achieved it.

Or add it to the Content Exchange section. Then people who are browsing that section can find your script, too!

rrichardson

I don't notify Orion. My script just does what Orion can't do (at least not without Application Manager). My script is attached. It uses nmap to see if the server is listening on port 3128. If it's not, then it verifies that the server is up by pinging it, and then calls another script to restart the server via SSH. I put both scripts in /usr/bin, so that they can be found. However, if you use cron to launch the script, then you must have a PATH statement in the script itself.

The script can be easily modified to check a different port, and contains a list of server IP addresses to check.

Note: nmap must be installed.

squidcheck scripts.zip

mrxinu

Do you really need to restart the server to sort out a squid problem?