Red Hat Bugzilla – Bug 58062
All NICs respond to ARP requests for any NIC in the system
Last modified: 2005-10-31 17:00:50 EST
Description of Problem:
Both of the LOMs (LAN-on-Motherboard, or onboard NICs) are responding to ARP
requests for each of the LOMs on the (forthcoming Dell) system.
If an ARP request is made to either of the LOMs for an IP address either of the
LOMs has it responds as the owner.
This leads to corruption of the ARP tables on switches wherein VLANning is
employed and the server spans both VLANs.
Attached are the logs from the switch, and from TCP/IP sniffing
UPDATE - Thomas Chenault 1/02/02
I have tested for this condition using other servers and NICs (Intel and
Broadcom) and found the behavior to be the same. Both Red Hat 7.1 and 7.2
behave as described above, responding to ARP requests on all receiving
I am aware of two circumstances under which the behavior can be observed:
1) when pinging from a switch to a server which exposes multiple physical
interfaces to the switch (as described in this issue).
2) when multiple physical interfaces are exposed to a single physical subnet
which is divided into multiple logical subnets.
I will begin discussions with our Linux team. I recommend that:
1) the issue be moved from the Dagger bucket to the Linux bucket.
2) the issue be lowered to sev. 3 due to limited impact.
UPDATE - Thomas Chenault 1/07/02
I have confirmed that the behavior is the same when with Red Hat 7.0 (2.2
Version-Release number of selected component (if applicable):
Red Hat Linux 7.0, 7.1 SBE, 7.2.
Steps to Reproduce:
1. See above
ARP requests for other NICs on multihomed system are responded to.
No ARP responses for the other NICs should be sent.
Created attachment 41931 [details]
Created attachment 41932 [details]
Created attachment 41933 [details]
switch console log
VLAN will most likely be supported as of the next RHL release; linux supports
vlans as of kernel 2.4.16.
If the switch gets upset then it's a problem already; I'm talking to our TCP/IP
guys about it.
This appears "as designed"; this failover behavior can be turned off with