Keep a log for total number of connections to a particular port from Foreign Address
Is there any log entries to find-out directly the total number of connections in server?
In some high connection high load servers, this log would be helpful to monitor and tune the server with number of connections on it. We can simply sort out the total number of connections in a port by using the command netstat. There isn’t any log entries with total number of connections. But, we will get the history of resource usage information by installing sar (Systat) on the server. Then, we can create a cronjob to monitor the server connections. In this post I am explaining the method to create a log for total number of connection to server. Before creating a script and setting cron, you must have the idea to use the command “netstat” to list total number of connections in server.
By considering the service Apache, we can sort it by using the port 80.
netstat -ntlp|grep :80|wc -l
netstat -ntlp|grep :80|wc -l 3385
Refer this for more about the command “netstat”, >> netstat command’s practical usages with example <<
If you want to monitor the total connection to your Apache service at times, create a cronjob to save this to a file as a log. Here I am using the command “date” to get the time details when the “netstat” taking the connection log. Please do follow these steps to create a log with connection details.
Step 1 : Create a file to get the log.
Step 2 : Create a script for the same.
2.1 –> Use the command ‘date’ for time details.
2.2 –> Use ‘echo’ to print your instructions.
2.3 –> Use ‘netstat’ for connection details.
echo "Time" date echo "Total no: of connection in port 80" netstat -ntlp|grep :80|wc -l echo ""
Step 3 : Change the file permission as executable.
chmod 755 connections.log
Step 4 : Test the script from the location.
./connection.txt Time Fri Jul 18 01:11:02 MSD 2014 Total no: of connection in port 80 1
Step 5 : Create a file to log the connection information.
Step 6 : Create a cronjob to execute this periodically.
crontab -e */30 * * * * /root/connection.txt >> connections.log
This will save the total number of connections to the file connections.log.