root@ubuntu:~# dstat
----total-cpu-usage---- -dsk/total- -net/total- ---paging-- ---system--
usr sys idl wai hiq siq| read writ| recv send| in out | int csw
0 0 99 0 0 0| 20k 4016B| 0 0 | 0 0 | 134 165
1 0 100 0 0 0| 0 0 | 0 0 | 0 0 | 55 85
0 0 100 0 0 0| 0 0 | 0 0 | 0 0 | 77 142
0 0 100 0 0 0| 0 0 | 0 0 | 0 0 | 45 84
0 0 100 0 0 0| 0 0 | 0 0 | 0 0 | 83 160
1 0 99 0 0 0| 0 0 | 0 0 | 0 0 | 46 86
2 1 97 0 0 0| 0 84k| 0 0 | 0 0 | 179 207
1 0 99 0 0 0| 0 0 | 0 0 | 0 0 | 107 226 ^C
root@ubuntu:~# tcpdump
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth1, link-type EN10MB (Ethernet), capture size 96 bytes
^C
0 packets captured
0 packets received by filter
0 packets dropped by kernel
root@ubuntu:~#
http://blog.chinaunix.net/uid-13746440-id-5755974.html