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Issue with Web(http) check

While implementing Simon we found out that we could use the Web (http) check in get mode with our Web site at http://www.web-a-la-carte.com.

The check works fine the first time but then all further checks fail. Investigating a little bit more, we found out that the request issued by Simon all but the first time might be badly formatted.

We moved from "get" to "head" and have our Web site availability check working so far.

We would like to be more precise on the Web server control and get notified only when the server no longer respond. The reason is that a nasty random bug in our Web server holds any further requests until the server is restarted when the bug happen.

We have written an Applescript that can cleanly stop and restart our apps and web servers when the bug occurs. We use Simon to launch the Applescript. But we only have to launch it when a time out occurs not when any other unavailability event occurs. So far we have not been successfull at using the "Smart change" approach.

Help is welcome.

David Sinclair's picture

Re: Issue with Web(http) check

Can you please clarify what you mean by "badly formatted". Does it appear to be a Simon bug, or is it an issue with your web server?

The "Get" mode is the normal mode that most people use with the Web (HTTP) service. I'm not aware of any issues with it, though it's conceivable that recent changes in the beta could have broken something.

If you want the test to only fail when it times out (or has a server error), just disable the Smart Change Detection option. You only need that if you want to check a subset of the page, or ensure that certain text is present.

Re : Issue with Web(http) check

Seems to be Simon bug. The site just works fine with all browsers. It just works fine during the first check. Any further check gets a RC 400.
You can test it yourself.

Just create an entry in Simon for http://www.web-a-la-carte.com with a Web check in get mode. Click the "Check now". The first time it works. Click "Check now" again. You get the failure (RC 400). Click the "Visit" button and it works.

Robert Ernens
HCTBA Consulting

David Sinclair's picture

Re : Issue with Web(http) check

The issue seems to be that your web server returns a session cookie on the first check, which Simon records, but your site gives a 400 error if that cookie is passed with subsequent checks.

The solution is for Simon to not record session-only cookies, since by definition each Simon check is a separate session. I've made that change, and it works with your site.

Thanks for your help!

Issue with Web(http) check

Thanks to you for your fast reaction.

Robert Ernens
HCTBA Consulting