The netstat command has been deprecated and replaced by the ss command in most of the Linux distributions.
It reads various ‘/proc’ files to gather information. It would take more time when there are lots of connections to display.
1) Checking the number of concurrent Apache connections
Run following ss command to find the total number of concurrent connections to Apache:
# ss -ant | grep -E ':80|:443' | wc -l 500
Alternatively, you can get Apache concurrent connection using netstat command as shown below:
# netstat -ant | grep -E ':80|:443' | wc -l 430
2) Checking concurrent connections of Apache in detail
Run the below ss command to see detailed information of Apache connections instead of counting it.
It shows the active internet connections on the server on port 80 & 443:
# ss -ant | grep -E ':80|:443' LISTEN 0 128 10.10.6.160:80 : 106.222.112.160:12650 TIME-WAIT 0 0 94.237.76.92:443 114.119.135.42:2366 TIME-WAIT 0 0 94.237.76.92:443 114.119.135.42:2406 TIME-WAIT 0 0 94.237.76.92:443 127.0.0.1:38400 ESTAB 0 0 127.0.0.1:38454 94.237.76.92:443 ESTAB 0 0 94.237.76.92:443 117.249.205.234:64685 ESTAB 0 0 94.237.76.92:443 192.99.9.25:33132 ESTAB 0 0 94.237.76.92:443 66.249.71.82:49611 ESTAB 0 0 94.237.76.92:443 106.222.112.160:12648 TIME-WAIT 0 0 94.237.76.92:443 127.0.0.1:38412 ESTAB 0 0 127.0.0.1:38402 94.237.76.92:443 TIME-WAIT 0 0 94.237.76.92:443 157.46.105.172:45656 TIME-WAIT 0 0 94.237.76.92:443 127.0.0.1:38340 ESTAB 0 151496 94.237.76.92:443 106.222.112.160:12656 TIME-WAIT 0 0 94.237.76.92:443 127.0.0.1:38332 TIME-WAIT 0 0 94.237.76.92:443 127.0.0.1:38396 ESTAB 0 0 127.0.0.1:38460 94.237.76.92:443 TIME-WAIT 0 0 94.237.76.92:443 127.0.0.1:38374 ESTAB 0 0 94.237.76.92:80 5.9.61.232:51082 ESTAB 0 0 94.237.76.92:443 60.8.123.152:64476 ESTAB 0 0 94.237.76.92:443 167.114.209.104:35758 ESTAB 0 0 94.237.76.92:80 106.222.112.160:12643 ESTAB 0 0 94.237.76.92:443 167.114.158.215:53270 ESTAB 0 0 94.237.76.92:443 66.249.71.147:56912 ESTAB 0 0 94.237.76.92:443 127.0.0.1:38454 ESTAB 0 0 94.237.76.92:443 127.0.0.1:38468 ESTAB 0 0 94.237.76.92:443 127.0.0.1:38402 TIME-WAIT 0 0 94.237.76.92:443 127.0.0.1:38366
Check the same information using the netstat command as shown below:
# netstat -ant | grep -E ':80|:443'
3) Listing Apache connections sort by IP
To count the number of connections currently active in Apache from each IP address and to sort them, use the following command:
# ss -ant |grep -E ':80|:443'|grep ESTAB| awk '{print $5}' | cut -d":" -f1 | sort | uniq -c | sort -nr
8 94.237.76.92
8 127.0.0.1
2 5.9.61.232
2 106.222.112.160
1 98.236.14.66
1 66.249.72.22
1 66.249.71.48
1 192.99.9.25
1 167.114.209.104
1 167.114.158.215
Similarly, you can find the same information using netstat command as shown below:
# netstat -ant |grep -E ':80|:443'|grep ESTAB | awk '{print $5}' | cut -d":" -f1 | sort | uniq -c | sort -nr
6 162.158.155.70
5 127.0.0.1
2 172.68.51.180
2 172.68.215.98
2 172.68.215.86
2 172.68.215.77
2 172.68.215.75
2 172.68.215.113
2 172.68.215.111
2 172.68.215.109
2 172.68.215.101
2 172.68.215.100
2 162.158.150.128
2 162.158.150.120
2 162.158.118.154
2 141.101.96.253
2 141.101.96.243
2 141.101.76.234
2 141.101.105.254
.
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Bonus Tips: 1) Counting running Apache processes in Linux
ps command is used to display all running processes in Linux system. Use the following format, if you would like to count the running Apache processes in Linux:
# ps -auxw | grep httpd | grep -v grep | wc -l 12
1.a) Listing Apache processes with ps
Use the following command to see the running httpd processes in Linux:
# ps auxw | grep httpd | grep -v grep nobody 7988 0.0 0.5 253280 23252 ? S 14:32 0:00 /usr/sbin/httpd -k start nobody 8050 0.0 0.6 253412 24276 ? S 14:33 0:00 /usr/sbin/httpd -k start nobody 8054 0.0 0.6 253280 23288 ? S 14:33 0:00 /usr/sbin/httpd -k start nobody 8158 0.0 0.6 253280 23296 ? S 14:33 0:00 /usr/sbin/httpd -k start nobody 8159 0.0 0.5 253280 23176 ? S 14:33 0:00 /usr/sbin/httpd -k start daygeek 8202 0.0 0.6 253416 23304 ? S 14:34 0:00 /usr/sbin/httpd -k start nobody 8203 0.0 0.5 253280 23052 ? S 14:34 0:00 /usr/sbin/httpd -k start nobody 8207 0.0 0.5 253280 23044 ? S 14:34 0:00 /usr/sbin/httpd -k start nobody 8213 0.0 0.6 253280 23300 ? S 14:34 0:00 /usr/sbin/httpd -k start nobody 8216 0.0 0.5 253280 23052 ? S 14:34 0:00 /usr/sbin/httpd -k start nobody 8218 0.0 0.6 253416 23304 ? S 14:34 0:00 /usr/sbin/httpd -k start nobody 8266 0.0 0.5 253148 23052 ? S 14:35 0:00 /usr/sbin/httpd -k start nobody 8267 0.0 0.5 253144 22800 ? S 14:35 0:00 /usr/sbin/httpd -k start nobody 8391 0.3 0.5 253144 22800 ? S 14:35 0:00 /usr/sbin/httpd -k start nobody 8393 0.5 0.5 253012 21776 ? S 14:35 0:00 /usr/sbin/httpd -k start nobody 8394 1.0 0.5 253144 22800 ? S 14:35 0:00 /usr/sbin/httpd -k start root 30500 0.0 0.0 227356 3584 ? Ss Jul25 2:33 /usr/sbin/httpd -k start
Let’s quickly look at the parameters
- Serverlimit – Maximum number of Apache processes
- StartServers – Number of processes to start when you start running Apache
- MinSpareThreads/MaxSpareThreads – Number of threads to keep idle without being killed
- ThreadsPerChild – Number of threads per process
- MaxRequestWorkers – Number of concurrent connections to be supported. This is the main directive that you need to change to increase max connections in Apache
- MaxConnectionsPerChild – Number of connections to be handled by each child before it is killed