View and kill processes in Ubuntu: 1, ps-e command 2, feng @ feng :~ $ Sudo netstat-antupActive Internet connections (servers and established) Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program nametcp 0 0 127.0.0.1: 631 0.0.0.0: * LISTEN 4672/cupsd tcp 0 0.0.0.0: 3000 0.0.0.0: * LISTEN 7082/ruby tcp 0 0 192.168.1.102: 41121 66.113.164.119: 80 ESTABLISHED 5709/firefox tcp 0 0 192.168.1.102: 44746 209.85.201.125: 5222 ESTABLISHED 6130/pidgin tcp 0 0 192.16 8.1.102: 54797 192.168.1.128: 3306 ESTABLISHED 7082/ruby tcp 0 0 192.168.1.102: 43466 64.4.34.77: 1863 ESTABLISHED 6130/pidgin tcp 0 192.168.1.102: 41999 64.233.189.19: 443 ESTABLISHED 5709/firefox tcp 0 0 192.168.1.102: 54900 58.251.60.53: 80 ESTABLISHED 6130/pidgin tcp 0 0 192.168.1.102: 34180 Timeout: 80 TIME_WAIT-tcp6 0 0: 1: 42801 ::: * LISTEN 6863/java udp 0 0 0.0.0.0: 68 0.0.0.0: * 5161/dhcli Ent udp 0 0 0.0.0.0: 5353 0.0.0.0: * 4625/avahi-daemon: udp 0 0 0.0.0.0: 56699 0.0.0.0: * 4625/avahi-daemon: processes that killed webrick: feng @ feng: ~ $ Sudo kill 7082 Method 2: for example, Firefox is now frozen and cannot send requests accordingly. Open a terminal and enter pgrep firefox to return a value, for example, 7198. Now input: kill 7198 to kill the Firefox process. You can also use the killall command. You can use the program name for killall. For example, enter the killall firefox 3 method. If the first two are not killed, run the kill-9 pid command.