When a monitoring check reaches or passes a specific threshold or value, an alarm is triggered and you'll receive a Warning or Critical email notification for the monitored resource. This article describes some simple troubleshooting steps that can help you diagnose the problem.
Ping checks typically monitor a server. If your ping check alarm is triggered, you should immediately try to contact your server using the ping command.
Issue the following command from an OSX Terminal window, Windows Command Prompt, or your favorite Linux shell:
ping <target_hostname or ip_address>
This ehow article, How to Read Ping Test Results, offers some good, general information on reading the results of the ping test.
The HTTP check is used to check websites. Try these preliminary troubleshooting steps if you receive a notification from an HTTP check:
Your browser will either return the page or it may return another error saying the site was unreachable or an error code from the web server. Common error codes include the following:
Run cURL, a common command line web page utility, against the website you are checking. This will return the contents of the web page to your terminal or shell window. You can explore curl's options to get more specific information, however a useful option is -I. This returns the target web page's headers and the response code from the web server. For example, enter this command in your terminal or shell window replacing your_domain with your actual domain:
curl -I http://www.your_domain.com
The output should look something like this:
HTTP/1.1 200 OK
Content-Type: text/html; charset=UTF-8
Last-Modified: Tue, 04 Sep 2012 20:00:05 GMT
P3P: CP="ALL DSP COR CUR ADMo DEVo TAIo PSAo PSDo IVAo CONi OTPi OUR NOR UNI"
Server: Apache Date: Tue, 04 Sep 2012 20:33:51 GMT
Connection: keep-alive Set-Cookie: target=us; path=/; domain=.your_domain.com Expires: Tue, 04 Sep 2012 21:00:00 GMT
TCP checks monitor ports. If an alarm is triggered for a TCP check, try to telnet to the target or scan your target for the open port.
Note: Make sure you are authorized to scan the target. Many network security groups view this as an attack on the open port.
Or access the service directly that is running on that port. For example, if it''s an SSH server, try to open an ssh session to the target host. If it's a MYSQL or MSSQL server try to connect to the database. Here's an example of how to telenet to the default port (3306) for MYSQL:
telnet mysql.myhost.com 3306
To exit telnet, type Ctrl ], press Enter, and then type "quit".
If you're unable to solve the problem using the steps outlined above, contact Rackspace Technical Support using the Cloud Control Panel. Your options for contacting Rackspace are as follows:
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