one-liner to see current internet bandwidth usage

doorbits · 10-31-2003, 04:41 PM

Hi, I'm looking for a one-liner (that is, please don't point me to a GUI monitoring utility like Gkrellm2 or Karamba) that prints out my current internet bandwidth usage.

I'm pretty sure this is possible. Using "cat" and that command line calculator and the /proc filesystem, somehow. I googled for a long time last night trying to find what file in /proc gievs me the current network usage, but I can't find it. I did a manual opening of most of the files, and I can't anything. This number is a combination of the upload speed and download speed, ie current internet bandwidth usage.

I know this is possible because I saw a site which had it's uptime and current internet bandwidth usage at the bottom of the page. I have read up on how /proc works also. I hope debian supports this.

I hope someone knows how to do this.

Thanks in advance!

ToniT · 10-31-2003, 06:01 PM

/proc/net/dev gives you cumulative statistics of how many packets transmitted and recieved.

If you want something more information, you have to watch the changes by yourself or use a toolbox like netdiag which does the things you probably want.

doorbits · 10-31-2003, 06:56 PM

Quote:

Originally posted by ToniT
/proc/net/dev gives you cumulative statistics of how many packets transmitted and recieved.

If you want something more information, you have to watch the changes by yourself or use a toolbox like netdiag which does the things you probably want.

I never said anything about packets, I said I was looking for current traffic speed.

Installed netdiag, none of the programs in it output to stdout, and a quick overview showed none that showed speed.

ToniT · 10-31-2003, 09:58 PM

Code:

toni@mario:~$ cat /proc/net/dev
Inter-|   Receive                                                |  Transmit
 face |bytes    packets errs drop fifo frame compressed multicast|bytes    packets errs drop fifo colls carrier compressed
    lo:489169465  742356    0    0    0     0          0         0 489169465  742356    0    0    0     0       0          0
  eth0:418515467 10567421    0    0    0     0          0         0 1610157716 8974064    0    0    0     0       0          0

There is also the byte count, you know.

except trafshow and statnet; both show the speed also.

If you want a oneliner:

Code:

perl -we 'sub getpkt { open DEV,"/proc/net/dev"; while(<DEV>) { if(/eth0/) { @line=split(/:|\s+/); close DEV; return $line[2]; }} close DEV; } my $pkts=getpkt(); sleep 5; print "Recieve rate is " .(getpkt()-$pkts)/5 . "\n";'

doorbits · 11-01-2003, 12:58 AM

Quote:

Originally posted by ToniT
[code]
except trafshow and statnet; both show the speed also.

If you want a oneliner:

Code:

perl -we 'sub getpkt { open DEV,"/proc/net/dev"; while(<DEV>) { if(/eth0/) { @line=split(/:|\s+/); close DEV; return $line[2]; }} close DEV; } my $pkts=getpkt(); sleep 5; print "Recieve rate is " .(getpkt()-$pkts)/5 . "\n";'

Yes, but at a quick glance I couldn't get either to output the total speed to stdout.

Thanks for this one liner, could you please update it so that it include the upload rate also, and thus shows the total speed? I wish I knew perl so I wouldn't have to ask.

Thanks! This one-liner is very complex!

ToniT · 11-01-2003, 05:59 AM

I had in mind to leave that as an exercise

But all right then:

Replace the word "$line[2];" with "$line[10]" to get the upload rate.
Replace the word "$line[2];" with "$line[2]+$line[10];" to get the whole throuhput
You might also want to change the printout to say something else than "Recieve rate is".

The numers here (2 and 10) refer to the fields in the contents of /proc/net/dev.

doorbits · 11-01-2003, 03:10 PM

Quote:

Originally posted by ToniT
I had in mind to leave that as an exercise

But all right then:
Replace the word "$line[2];" with "$line[10]" to get the upload rate.

Replace the word "$line[2];" with "$line[2]+$line[10];" to get the whole throuhput

You might also want to change the printout to say something else than "Recieve rate is".

The numers here (2 and 10) refer to the fields in the contents of /proc/net/dev.

Then add the /1024 to get it in k/sec....sweet! it works!

Thanks so much ToniT! I would have never figured this out by myself. I understand some parts of this line, thanks for pointing me to make the changes myself.

Code:

perl -we 'sub getpkt { open DEV,"/proc/net/dev"; while(<DEV> ) { if(/eth0/) { @line=split(/:|\s+/); close DEV; return $line[2]+$line[10]; }} close DEV; } my $pkts=getpkt(); sleep 5; print "Network usage " .((getpkt()-$pkts)/5)/1024 ; print " K/sec". "\n";'