ubuntu的系统怎么查看每日流量啊

vnstat     {:7_742:}

应该是安装楼上说的那个东西  在用命令查询

谢~
不过我只是安装好了，到了设置那一个步骤之后就好像没有什么说明已设置完成的反应...
在使用那部输入那些代码后出现三个错误...
求问怎么解决~{:7_741:}

装的vnstat？ 什么错误啊

root@ks3290035:~# chmod o+x /usr/bin/vnstat
root@ks3290035:~# sudo chmod o+x /usr/bin/vnstat
root@ks3290035:~# vnstat -u -i 23880
Error: Unable to read database "/var/lib/vnstat/23880".
Error: Unable to get interface "23880" statistics.
Error: Interface "23880" couldn't be found.
Only available interfaces can be added for monitoring.

The following interfaces are currently available:
    dummy0 bond0 eth0 ip6tnl0 lo sit0 tunl0
root@ks3290035:~# chmod o+wx /var/lib/vnstat/
root@ks3290035:~# vnstat -u -i 23880
Error: Unable to read database "/var/lib/vnstat/23880".
Error: Unable to get interface "23880" statistics.
Error: Interface "23880" couldn't be found.
Only available interfaces can be added for monitoring.

The following interfaces are currently available:
    dummy0 bond0 eth0 ip6tnl0 lo sit0 tunl0

应该是这样吧
vnstat -u -i ath0

root@ks3290035:~# vnstat -u -i ath0
Error: Unable to read database "/var/lib/vnstat/ath0".
Error: Unable to get interface "ath0" statistics.
Error: Interface "ath0" couldn't be found.
Only available interfaces can be added for monitoring.

The following interfaces are currently available:
    dummy0 bond0 eth0 ip6tnl0 lo sit0 tunl0
感觉上面的步骤还有问题...但是不知道哪里有问题...

{:7_741:} 看错了 是vnstat -u -i eth0

唔~可以了~谢~
但是这个只能查安装了vnstat了以后的流量的？之前的还是不知道诶...{:7_741:}

之前的我就不会{:7_734:}