netstat command for popular IP addresses OK in CentOS 6, fails in CentOS 7

In CentOS 6 w/ OpenVZ 2.6.32, this command outputs IPs with the highest number of connections against port 22, e.g: [root@legovz ~]# netstat -antu | grep :22 | grep -v LISTEN | awk '{print $5}' | cut -d: -f1 | sort | uniq -c | sort -n 2 217.20.114.121 3 0.0.0.0 3 58.242.82.6 [root@legovz~]# Under CentOS 7, w/ OpenVZ 7, the output is always as follows, despite the fact I know there is lots of traffic on port 22: [root@ovz7 ~]# netstat -antu | grep :22 | grep -v LISTEN | awk '{print $5}' | cut -d: -f1 | sort | uniq -c | sort -n 1 0.0.0.0 [root@ovz7 ~]# What I need to do differently, to achieve the same result with CentOS 7.? If I can't, why?