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 04-12-2013, 05:05 AM   #1
LQ Newbie
Registered: Apr 2013
Posts: 2

Rep: Reputation: Disabled
[RedHat] ARP issue


[Edit] Know issue for QRadar 7.1 running on RedHat 6.2.

I am setting up a new server with two network interfaces.
These interfaces are on different subnets, and connected to the same firewall.

I'm trying to reach a remote IP.
It works fine from the first interface.

The second interface however, is making ARP requests instead of contacting the default gateway.
Using the same cable, and a laptop with the same IP setting as this second server interface, I can join the remote IP, so I would say it is not a connectivity/firewall issue.

I have tried several things without success so far

Any idea?

Thank you


Last edited by Wanou85; 04-17-2013 at 06:24 AM. Reason: OS added
Old 04-13-2013, 09:21 AM   #2
Registered: May 2008
Location: Toronto
Distribution: Centos && Debian
Posts: 347

Rep: Reputation: 34
The second interface however, is making ARP requests instead of contacting the default gateway.
Even to contact default gateway, it needs to send ARP request to know MAC address of default gateway. When a host needs to send packet/Frame to default gateway, at first it needs to know MAC address of default gateway. Host looks first at its own ARP table in cache. If it could not find MAC address of default gateway in its own MAC address table, then it needs to send ARP broadcast. So there is nothing wrong if it sends ARP request.

There may be misconfigured networking or routing issue on the "new server". You can show here routing table and network interface configuration to get the solution. Also specify which version of RedHat you are using.
Old 04-17-2013, 06:23 AM   #3
LQ Newbie
Registered: Apr 2013
Posts: 2

Original Poster
Rep: Reputation: Disabled
Hello, thank you very much for your reply.
I have heard from the OS provider (IBM) and this is a know issue for the specific OS that I'm using.
It cannot do IP spoofing in certain scenarios such as the one I'm using.
Product: Qradar 7.1
Thanks again!


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
arp issue ---> ? ( at <incomplete> on bond1 drManhattan Linux - Networking 2 09-17-2011 03:14 PM
ARP flux issue with Ubuntu 9.10 hydrogen18 Linux - Networking 1 06-27-2010 10:23 AM
Wireless Internet trouble, ARP issue? Titan8990 Linux - Wireless Networking 1 08-25-2008 11:11 PM
arp issue Net_Spy Linux - Networking 5 01-17-2008 02:08 AM
arp issue dinisco Linux - Networking 0 04-03-2007 11:41 AM > Forums > Linux Forums > Linux - Networking

All times are GMT -5. The time now is 10:05 AM.

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