server down notifications

how?

[omoutop]

Hello and thank you for any tips/advice.

We own two servers... one is the main server that hosts some domains, the other is the secondary one, used for development/testing purposes.

Is it possible for the second server to check if the main one is down (for any reason whatsoever) and alert us with an email and an sms?

[rominosj]

Do you mean you own two web servers? or two hosting accounts, maybe at different hosting companies?

[omoutop]

two webservers

[Swaraj]

As your second server is not not connected online then I don't think its possible. I would suggest you to go for virtualization on the same server.

[lucy24]

Did I miss something? "Development/testing" doesn't have to mean offline, or even strictly localhost. I assumed that Server B is online, you just don't have any active domains living on it.

Are you looking at a continuous connection between the two? Or something like a timed routine where Server B automatically checks in on Server A every so often and automatically sends you an e-mail if there's a problem? Even something as simple as Server B requesting a file, and reporting back if it gets a 5xx error.

[omoutop]

lucy you are correct... both serves are online and active.
The testing server has no active domains.

Your approach seems correct. Either file request or continuous connection or anything else.

I have no idea how this can be accomplished, so i am asking for guidelines to start searching.
Is there some technique? Some formal name for this? What should i ask the server admin/support to do/install/activate?

Also, can we get sms message along with the email notification?
Can we have this error 'report' only for status 500 OR can it be expanded to inlude mysql downtime also? (too many connections for example, or whatever else may 'hang' the server)

[lucy24]

I keep thinking robots. Or, uhm, a spider with only one leg. I don't personally have the remotest idea how it's done. But aren't there undergraduate computer science classes with "this week's assignment-- make a robot"? It can't be all that hard. You're just making a robot that visits one site at regular intervals, and then does whatever it is robots do when they find what they're looking for.

[omoutop]

mmm robots eh? A simple one, just to test headers for 404 or 500 for starters. Yes, this can be done even by me :)
Keep wondering why i didn't think of this.

Thanks for the idea Lucy.

[tangor]

Something as simple as a chron job request to secondary will accomplish this.

[Jonesy]

nagios [nagios.org ]