| |
|
 |
|
 |
|
|
|
| |
|
|
xen-devel
Re: [Xen-devel] ARP problems in -testing?
> I just tried this on a dedicated server located at thePlanet in Texas; I
> think this is an issue that combines the following:
>
> - No MAC address specified causes a random MAC address to be selected at
> domain create time
> - The upstream router has a local ARP cache
> - The host system's ARP cache for addresses on the virtual NIC for the
> instance is blown out when the virtual interface disappears when the
> domain is destroyed
>
> This seems to explain why tcpdump shows packets going to the VM's IP, but
> TCP sessions and ICMP packets don't get a response - the switch still
> knows the "old" MAC address, but the first outbound packet to the outside
> world implicitly eradicates the old ARP-cache entry. I don't think this is
> Xen's fault at all, just a property of the implementation of ARP
> resolution. I just happened to notice that the MAC shown in incoming
> packets didn't match the current MAC address (based on ifconfig's output),
> so this is my current theory on what's happening.
Thanks for the detailed answer -- I've added it to the Xen FAQ
(http://www.cl.cam.ac.uk/netos/xen/faq.html). I guessed it would
probably be something like this...
Cheers,
Keir
-------------------------------------------------------
The SF.Net email is sponsored by: Beat the post-holiday blues
Get a FREE limited edition SourceForge.net t-shirt from ThinkGeek.
It's fun and FREE -- well, almost....http://www.thinkgeek.com/sfshirt
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.sourceforge.net/lists/listinfo/xen-devel
|
|
|
| |
|
Home