Question

I have a micro instance on EC2, and I deployed a wordpress website on it. But the site will be down about every two days because mysql is killed, so visitors get “500 Internal Server Error”.
And I need log in AWS, and reboot the instance. I know I should optimize the apache configuration, but rebooting the instance will be a simple solution.
I’m using a service which can monitor my website, and when site is down, they will send me a email, but they can’t reboot the EC2 instance.

I configure the apache like below, it works now:

StartServers       1
MinSpareServers    1
MaxSpareServers    5
MaxClients        10
MaxRequestsPerChild  4000

Answer 1

Maybe you can create a bash, and put it in /etc/cron.hourly to run it every hour.

Here is the content of bash.

#!/bin/bash
#Replace MYSQL_PORT with the real port number.
netstat -na | grep LISTEN | grep MYSQL_PORT
if [ $? != 0 ]; then
  reboot
fi

Don’t forget to make it executable just like the below.

chmod 0755 /etc/cron.hourly/monitor_mysql.sh

Moreover you can make it check more frequently by create a file in /etc/cron.d/ like the below to check every 5 minutes.

# vi /etc/cron.d/monitor_mysql
*/5 * * * *     root /path/to/monitor_mysql.sh