Solved

How to turn off promiscuous mode on a NIC?

Posted on 2004-04-27
7
2,291 Views
Last Modified: 2012-06-21
My boss is getting tons of traffic going through his NIC, and would like it to stop. I have determined that his card is most likely running in promiscuous mode and is accepting all the packets thaqt come through the network. How do I turn this off? I can't find the option anywhere.

He is using Windows 2000

Thanks.
0
Comment
Question by:StickyDragon
7 Comments
 
LVL 7

Expert Comment

by:magus123
ID: 10929868
0
 
LVL 11

Expert Comment

by:PennGwyn
ID: 10931991
What tool is claiming that there are lots of packets coming through?

What does the network infrastructure look like (hubs, switches, etc)?
0
 

Author Comment

by:StickyDragon
ID: 10932127
This is when you right-click the LAN connection and choose "Status" from the drop-down.
0
Connect further...control easier

With the ATEN CE624, you can now enjoy a high-quality visual experience powered by HDBaseT technology and the convenience of a single Cat6 cable to transmit uncompressed video with zero latency and multi-streaming for dual-view applications where remote access is required.

 
LVL 2

Expert Comment

by:dramatix01
ID: 10934047
From the little bit of information that you have given it is very difficult to truly determine what the problem is.  It sounds like you are trying to treat the symptom and not the problem.

If you could answer some of the following questions we may be better able to help you:

1. How big is your network?
2. As PennGwyn asked, what type of network hardware are you using? (switches, hubs, etc.)
3. How old is the hardware attached to your network?

You can see where I'm going with this.  Any other information that you could offer would make this problem much easier to solve.

You may also want to stick a sniffer on your network to see if you have a chattering NIC or an employee that loves to watch or listen to streaming media while working.

Regards,
Dave...
0
 
LVL 1

Accepted Solution

by:
axelt earned 30 total points
ID: 10936534
NIC's don't just turn on promiscous mode by themselves - check for viruses.

If you want to know where the traffic is coming from, download ethereal from http://www.ethereal.com/distribution/win32/
Install winpcap3.0 from the same location before installing ethereal.

When capturing - turn promiscous mode off. Stop all applications.
If you use hubs - buy switches






0
 

Author Comment

by:StickyDragon
ID: 10941338
Definitely no viruses, we have Norton corporate, up to date definitions. Tried Ethereal. Neat program, seems that my boss is getting mostly TCP packets (whereas as I get TCP/UCP/ARP pretty evenly (And IPX for some reason, even though it isn't used). He seems to have a lot of TCP traffic coming from the Exchange server for one, and I don't for some reason. Why would this traffic be sent to one PC and not another?

1. We have about 150-200 computers
2. We have switches and hubs (all 3com rack-mount ones), but we are all connected into the same hub.... I did however move him to a switch and he had the same problem still.
0
 

Author Comment

by:StickyDragon
ID: 10942402
Turns out it was nothing more than a driver issue with 3Com 3C920 cards! Update your drivers if you ever run into this problem.
0

Featured Post

Netscaler Common Configuration How To guides

If you use NetScaler you will want to see these guides. The NetScaler How To Guides show administrators how to get NetScaler up and configured by providing instructions for common scenarios and some not so common ones.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
eigrp - not allow a subnet from advertising 1 58
Wired Network vs Wireless 12 66
SIP / Streaming - real time communications testing 8 89
Manage ASA using outside IP 14 61
Join Greg Farro and Ethan Banks from Packet Pushers (http://packetpushers.net/podcast/podcasts/pq-show-93-smart-network-monitoring-paessler-sponsored/) and Greg Ross from Paessler (https://www.paessler.com/prtg) for a discussion about smart network …
For many of us, the  holiday season kindles the natural urge to give back to our friends, family members and communities. While it's easy for friends to notice the impact of such deeds, understanding the contributions of businesses and enterprises i…
Viewers will learn how to connect to a wireless network using the network security key. They will also learn how to access the IP address and DNS server for connections that must be done manually. After setting up a router, find the network security…
This video gives you a great overview about bandwidth monitoring with SNMP and WMI with our network monitoring solution PRTG Network Monitor (https://www.paessler.com/prtg). If you're looking for how to monitor bandwidth using netflow or packet s…

792 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question