I am using a Linux server hosted on AWS and due to less amount of RAM available the website goes down and I get a "Error establishing connection to database" error.
I have to restart MySQL everytime this happens.
Can we automate this process?
The command I use to restart the LAMPP server is:
sudo /opt/lampp/lampp restart
Use a bash script to monitor the mysql port and restart it if it is down
Just to demo how it works
The nc command checks that port 3306 (mysql port) is contactable
If it is then $? is set to zero, so this counts as "up"
otherwise $? is down. You may wish to use a different command instead of "nc", for example
echo "select 1;" | mysql to attempt to run a do nothing mysql command
while [ 1 ] do sleep 1 nc -z localhost 3306 if [ $? == 0 ]; then echo "up" else echo "down" fi done
The actual version you might use could look like this
while [ 1 ] do sleep 10 nc -vz localhost 3306 if [ $? != 0 ]; then /opt/lampp/lampp restart fi done
You can leave a window open (maybe using the "screens" command too) and run this 24x7
If you can increase the time interval to 1 minute then it would be ok to run out of cron like this
in crontab ( to run every minute)
* * * * * /path/to/script
#!/bin/bash nc -vz localhost 3306 > /dev/null 2>&1 if [ $? != 0 ]; then /opt/lampp/lampp restart fi