Latest LQ Deal: Linux Power User Bundle
Go Back > Forums > Linux Forums > Linux - Networking
User Name
Linux - Networking This forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.


  Search this Thread
Old 05-28-2009, 09:01 AM   #1
LQ Newbie
Registered: Oct 2008
Posts: 8

Rep: Reputation: 0
Swamped with NetBios Broadcast Traffic

We have a CentOS linux server running Samba with Fedora Active Directory. Since yesterday, our subnet was swamped with netbios broadcast traffic - about 2-6Mbps... just wondering if there's any suggestions where we could start to try and resolve the problem?
Old 05-28-2009, 02:37 PM   #2
Registered: Apr 2009
Location: Largo, Florida
Distribution: Slackware
Posts: 208

Rep: Reputation: 35
My first reaction is either something is horribly broken, or you are actually seeing Netbios traffic over IP. Most commonly seen in Windows peer to peer communications. IE: IP ports 137 and 138.

You did not say which program you're using to see the traffic. You should be able to see a source MAC address in the trap. If you have a managed switch you should be able to determine the location of the source MAC address. Or, run nmap mysubnet/mask -p 138.

Example: nmap -p 138

This will list all the IP and MAC's, as well as all hosts with the netbios port open.

Last edited by Suncoast; 05-28-2009 at 02:40 PM.
Old 05-28-2009, 10:37 PM   #3
LQ Newbie
Registered: Oct 2008
Posts: 8

Original Poster
Rep: Reputation: 0
I am using iptraf to view the traffic - majority of the traffic is on UDP138.

Actually - we found the problem - there was a patch cable plugged in as a loop...


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
DHCP Offer is not a broadcast traffic when using a DHCP Relay, why? jayadhanesh Linux - Networking 1 03-23-2009 09:17 AM
NFS traffic over broadcast -- normal or not? kpj104 Linux - Networking 1 12-15-2008 04:44 PM
promiscuous mode not working (hub) - can only see broadcast traffic lardus Linux - Networking 11 05-16-2005 05:22 AM
Forward netbios broadcast packets atlesn Linux - Networking 0 07-26-2004 10:37 AM
netbios traffic odious1 Linux - Networking 1 12-01-2003 12:13 PM > Forums > Linux Forums > Linux - Networking

All times are GMT -5. The time now is 07:53 PM.

Main Menu
Write for LQ is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration