Respuestas:
Ifstat:
rilindo@ubuntu:~$ sudo apt-get install ifstat
[sudo] password for rilindo:
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
ifstat
0 upgraded, 1 newly installed, 0 to remove and 3 not upgraded.
Need to get 23.4kB of archives.
After this operation, 94.2kB of additional disk space will be used.
Get:1 http://us.archive.ubuntu.com/ubuntu/ lucid/universe ifstat 1.1-8 [23.4kB]
Fetched 23.4kB in 0s (34.6kB/s)
Selecting previously deselected package ifstat.
(Reading database ... 92838 files and directories currently installed.)
Unpacking ifstat (from .../ifstat_1.1-8_amd64.deb) ...
Processing triggers for man-db ...
Setting up ifstat (1.1-8) ...
rilindo@ubuntu:~$ ifstat
eth0 br0 virbr0 vnet0 vnet1 vnet2 vnet3 vnet4
KB/s in KB/s out KB/s in KB/s out KB/s in KB/s out KB/s in KB/s out KB/s in KB/s out KB/s in KB/s out KB/s in KB/s out KB/s in KB/s out
4.67 5.21 3.67 5.05 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3.93 4.59 0.38 0.74 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3.93 4.59 6.19 8.30 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3.93 4.59 3.03 4.33 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
Otro buen lugar para considerar se llama iftop , que mostrará conexiones y bps y tiene algunas características bastante decentes.
Yo uso iptraf, puedes configurarlo para que use Bits o Bytes.