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Introducing Simon 5!

Simon version 5 is now available. It is a massive update, introducing a much-requested feature: syncing the Simon data between multiple Macs, plus a Simon Status service, a Link Checker filter, improved Find filter, iMessage and Speak Error notifiers, a new app icon, and much more.

Important: please note that Simon 5 requires a minimum of macOS 10.12 (Sierra), and is a paid upgrade from Simon 4. Purchasers since September 1, 2020 automatically get a version 5 license (that also works in previous versions).

Read the Simon What's New page for details.

FTP Service and IIS - Consistent False Failures

So we've been using Simon for some time now and everything works great. I really love this application! However, in all of my monitoring I have two FTP servers running and need to have Simon constantly check to make sure the FTP services are online and working.

The Good: 95% of the time FTP service works just fine IF Simon is running within the same network internally as the FTP server is on. 85% of the time FTP service works IF Simon is offsite trying to access the FTP server over the Internet just as everyone else would do.

The Bad: Unfortunately, this FTP service is running from IIS. Which shouldn't matter, but I've read / heard a lot of bad things about Microsoft's little FTP server services.

The Ugly: "Error occurred: POSIX error: Connection reset by peer" and "Error occurred: lost network connection"... These two errors happen at least once or twice a day from the Simon box sitting on the same LAN as the FTP box; but four times as much with the Simon sitting offsite accessing the FTP site via the Internet. Sending me false failures. I've set the threshold for failures and multiple failures up as high as I can pretty much go, any further (let me know after xx failures) would result in a highly delayed report of a real failure.

The FTP service does not seem to bother any live active connections through other applications such as Cyberduck (Mac), or SmartFTP (Windows), or even the ftp command via Unix while these failures happen.

Could this be an IIS issue? Simon issue (which I'm assuming uses the Unix FTP command for its checking)? or something else? Anyone else out there have this happen to them? Able to figure it out?

We run another application called PageSentry which monitors these same FTP sites using the EXACT same method and it has never EVER reported a false outtage like Simon does, I've began wondering if there are any possibilities of how Simon checks ... like an active versus passive FTP connection.

Anyways, any feedback would be appreciated. Thank you.

Jessee Holmes

David Sinclair's picture

Re: FTP Service and IIS - Consistent False Failures

I'm glad you like Simon, but am sorry the FTP tests aren't reliable with your server.

Simon has two FTP services built-in: "FTP" and "FTP Directory Listing". Which one are you using?

The "FTP" service doesn't use the unix ftp command; it works like the "Web (HTTP)" service, connecting to the server via high-level Cocoa networking functions.

The "FTP Directory Listing" service is a Script-based one, which does use the unix ftp command. You can see what it does via its Edit Service window.

oranges2apples's picture

Sorry for the late response.

Sorry for the late response. We use the FTP service.

I'll try switching over to the FTP Directory Listing and see how that handles stuff.

Jessee Holmes

oranges2apples's picture

RE: FTP Service and IIS - Consistent False Failures

So I finally got this working correctly. I used it like you said, but not long ago, we had a hardware failure on the machine and Simon never notified us that it could not access the FTP directory through the FTP Directory Listing service.

This concerned me greatly and in looking into it, whether the machine was accessible or not, Simon would never come back with a failure.

So with the FTP service failing constantly with a Windows machine and the FTP Directory service never failing ever, I began looking at other methods of checking if this server was running or not.

Using an applescript seemed to be the inevitable choice for me. My other idea was just host a dummy IIS website and check against that to ensure the computer itself was still running (although this doesn't confirm the service is running).

Knowing that either of those two options would do the trick, I still wanted to understand why FTP Directory Listing service didn't seem to work at all. Without any knowledge of the results I was getting back, I attempted to play with the "Smart Change" feature and put characters in there. Once I had the correct characters (the characters returned from the FTP server via the script the service runs), this service worked perfectly. When the server was running, the check came back with a success. When the server was offline, the service failed. PERFECT!

The reason for my reply here is just to possibly help anyone else that may run into this issue and want a simple check of wether their FTP server is working or not.

My start character was 'd' and my end character was '-' in the Smart Change detection area. This is because 'd--------' is returned to Simon via the FTP server. I tried making a folder and using it's name, but that didn't work (no clue why).

Seeing the results of what's returned to Simon in a log window of some kind would be a great convenience.


David Sinclair's picture

RE: FTP Service and IIS - Consistent False Failures


Thanks for the follow-up. I'm glad you were able to get it working satisfactorily.

Using Smart Change Detection makes sense, to confirm that what is returned is what is expected. Note that you could have also just entered "d--" in the Start text and left the End text blank; that'd fail if that text isn't found anywhere in the output.

Regarding seeing the results of the FTP Directory Listing test, you can do that easily — simply click the Preview button.

oranges2apples's picture

RE: FTP Service and IIS - Consistent False Failures

Haha, thanks! The preview option was the perfect "easy button" I was searching for, for over an hour! :)

And good to know about having text in the Start text and the End text blank, I figured it'd work that way, but I was just happy I got it working in the end, so I left it alone.

This product has been beyond outstanding for us! I recommend it to anyone I can!