measuring traffic with netstat

pfrancois · 02-13-2009, 04:26 AM

Hello

The output of

Code:

netstat -e -i | awk '/^eth/,/^$/'

gives me

Code:

eth0      Link encap:Ethernet  HWaddr [...]  
          inet addr:192.168.[...]  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: [...]/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:183698 errors:0 dropped:0 overruns:0 frame:0
          TX packets:105432 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:219946959 (219.9 MB)  TX bytes:12666864 (12.6 MB)
          Interrupt:11 Base address:0x3000

which gives me an idea of my bandwidth consumption since the system is up, I suppose.

I would like to know:

a) where netstat is finding the information about RX and TX bytes, and

b) if this information is reliable.

An other option is to tell me how to browse the code of netstat.

Thanks in advance.

******* · 02-13-2009, 05:11 AM

Quote:

Originally Posted by pfrancois

where netstat is finding the information about RX and TX bytes, and if this information is reliable.

Anything "alive" get shown through /proc. If you mean reliability as in any 32 or 64-bit counters resetting then you could use an external tool to tally like 'vnstat'?

{BBI}Nexus{BBI} · 02-13-2009, 05:21 AM

Quote:

Originally Posted by pfrancois

a) where netstat is finding the information about RX and TX bytes

From the /proc directory.

Quote:

b) if this information is reliable.

In what sense? and for what purpose?

Quote:

An other option is to tell me how to browse the code of netstat.

Open the netstat binary with vi (or your preferred) editor.

pfrancois · 02-13-2009, 07:13 AM

Quote:

Originally Posted by {BBI}Nexus{BBI}

From the /proc directory. In what sense? and for what purpose?

OK, I supposed that, but I am looking in which file specifically.

Quote:

Originally Posted by {BBI}Nexus{BBI}

Open the netstat binary with vi (or your preferred) editor.

No, I mean I want to browse the source code of netstat, obviously

, online if possible, v.gr with a browser through http without downloading a tarball, expanding it, etc...

Thanks anyway for the reactions.

nx5000 · 02-13-2009, 07:20 AM

/proc/net/netstat on my kernel. But might be somewhere else in /proc/net. /proc/net/tcp gives active tcp connections.
Yes, it's reliable.

pfrancois · 02-13-2009, 08:12 AM

Quote:

Originally Posted by nx5000

/proc/net/netstat on my kernel. But might be somewhere else in /proc/net. /proc/net/tcp gives active tcp connections.
Yes, it's reliable.

Thanks nx5000