Network activity monitor

alpha754293 · 05-16-2006, 10:39 AM

Is there a way to monitor the network activity on a given interface?

I have a Netgear GA311 (RTL8169 chipset) GbE NIC and I want to find out what the link status is on the card.

Here's the output from dmesg:

Code:

ip_tables: (C) 2000-2002 Netfilter core team
r8169 Gigabit Ethernet driver 1.2 loaded
divert: allocating divert_blk for eth0
r8169: PCI device 01:07.0: unknown chip version, assuming RTL-8169
r8169: PCI device 01:07.0: TxConfig = 0x4000000
eth0: Identified chip type is 'RTL-8169'.
eth0: RealTek RTL8169 Gigabit Ethernet at 0xf8dba000, 00:09:5b:8d:98:13, IRQ 11
eth0: Auto-negotiation Enabled.
eth0: 1000Mbps Full-duplex operation.
ip_tables: (C) 2000-2002 Netfilter core team

and here's the output of from ifconfig:

Code:

eth0      Link encap:Ethernet  HWaddr 00:09:5B:8D:98:13
          inet addr:192.168.1.14  Bcast:192.168.1.255  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:1066806 errors:0 dropped:0 overruns:0 frame:0
          TX packets:798133 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:100
          RX bytes:859223517 (819.4 Mb)  TX bytes:0 (0.0 b)
          Interrupt:11 Base address:0xa000

I tried playing around with txqueuelen and trying to set that to 1000 but that actually ended up slowing it down.

I also reinstalled the driver from Realtek, and I haven't been able to get better than an erratic write rate (between 5-15% of GbE) and a sustained 9% read (from the server).

Thoughts?

brianthegreat · 05-16-2006, 10:55 AM

Ethereal will monitor the protocols that are traveling over the card. Which will help regardingthe amount of data that you arte passing.

alpha754293 · 05-16-2006, 11:27 PM

Quote:

Originally Posted by brianthegreat

Ethereal will monitor the protocols that are traveling over the card. Which will help regardingthe amount of data that you arte passing.

Well, I see that the ifconfig command gives me a total throughput, but I am looking for rate of throughput rather than total.

And I don't know if ethereal would necessarily do that (because it doesn't necessarily flag all packets coming in and out of the system).

When I was running Solaris, I was able to correlate the disk I/O meter with the link speed and throughput.

And even windows has a network monitor that can track throughput, so I would have figured that Linux (RH9) should have something that can do the same task, right?