Tools to monitor the performance of your Linux OS

1 - top --> CPU usage, memory usage, swap memory, Cache, Buffer Size, PID process user commands.
2 - vmstat -> Virtual Memory Statistics
3 - lsof -> open files list
4 - tcpdump-i eth0 -> Packet Analyzer.
5 - netstat-a -> Network Statistics.
6 - htop -> Process Monitoring.
7 - iotop -> Monitor Linux Disk I / O
8 - iostat -> Statistics in / out.
9 - iptraf.ng -> realtime monotorización lan / ip
10 - Psacct or Acct -> monitor of user activity
11 - Monit -> Linux Processes and tracking services.
12 - NetHogs -> Monitor for process-network bandwidth
13 - iftop - Bandwidth Control Network.
14 - Monitorix - System and Network Monitoring
15 - Arpwatch - Ethernet Activity Monitor - ARP spoofing