From: Markus Hennig <mhennig@as...> - 2002-07-21 20:23:51
i use a testbed with several UMLs, every with more then two network =
interfaces connected to a uml_switch,
e.g. host A with 1 interface connected to a uml_switch and host B with 3 =
If host A sends a ARP request for the IP of the first interface of B all =
3 interfaces of B will answer with
a ARP replay: "requested IP is MAC address ...".
So i got three different answers and a wrong one will be used in the arp =
Is this a specific "switch daemon interface" behavior?=20
If yes, where is efficient place to change this (only the correct NIC =
should send a ARP reply)?
[yes, proxy_arp is 0]
From: David Coulson <david@da...> - 2002-07-22 01:31:25
Markus Hennig wrote:
> If host A sends a ARP request for the IP of the first interface of B all 3 interfaces of B will answer with
> a ARP replay: "requested IP is MAC address ...".
> So i got three different answers and a wrong one will be used in the arp table (/proc/net/arp).
uml_switch is purely a transport - it doesn't do anything else. Linux
will ARP for all IPs it has on any interface when an ARP request is seen
on a interface. Thusly, when you have three NICs, all with different
IPs, connected to any individual switch, they will all respond to ARP
requests for any one of their IPs. I read a discussion as to whether or
not this was the correct implimentation, but I can't recall where I saw it.
If you've got more than one eth interface on UML, and they're on
seperate networks, why not run more than one uml_switch instance?
David Coulson http://davidcoulson.net/