[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] Stimulating domains to send gratuitous ARPs


  • To: "Graham, Simon" <Simon.Graham@xxxxxxxxxxx>
  • From: "Zhu Han" <schumi.han@xxxxxxxxx>
  • Date: Thu, 5 Jul 2007 17:03:50 -0400
  • Cc: xen-devel@xxxxxxxxxxxxxxxxxxx, Ian Campbell <Ian.Campbell@xxxxxxxxxxxxx>
  • Delivery-date: Thu, 05 Jul 2007 14:01:42 -0700
  • Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=k0762k9Zt4D5X5hh+U5V3+HXgAlXczAsx/OzKsOGP+8/jfGkXSD2oboUqpg5OXS6TycyUAQ0FPs70oY5zf6zQikC6DG1v0SM6hgs5DdUAmW0Fe4Age+oPhNeO3OF0UzC6b4Vhe5UV9FnHUk0fhTp+tpP3i7NCdxJJBJsmL7ZTao=
  • List-id: Xen developer discussion <xen-devel.lists.xensource.com>

On 7/5/07, Graham, Simon <Simon.Graham@xxxxxxxxxxx> wrote:
Whilst I might agree that from a purist point of view having netfront do this 
is a violation of layering, it's already accepted in some other upstream 
drivers -- bonding for example; this virtual network interface driver will send 
gratuitous ARPs for the IP address associated with the bond and for any VLANs 
layered directly on top of the bond when failing over (it just wont send ARPs 
for things above the bridge if it is plugged into a bridge).


I guess the user mode helper should be inside DOM0 unless you wanna
ask the user to intall some extra tools as vmware does, considering
about HVM domain.

The user mode helper in DOM0 should watch the connect status between
netback and netfront. If it becomes connected, then sends out an fake
ethernet frame, not an fake arp reply because you can't know the IP
address.

Xentore can provide the mac address of netfront but netfront has to
register set_mac_address method to update it when the user try to
modify it.

Simon

> -----Original Message-----
> From: Ian Campbell [mailto:Ian.Campbell@xxxxxxxxxxxxx]
> Sent: Thursday, July 05, 2007 3:46 PM
> To: Graham, Simon
> Cc: xen-devel@xxxxxxxxxxxxxxxxxxx
> Subject: Re: [Xen-devel] Stimulating domains to send gratuitous ARPs
>
> On Thu, 2007-07-05 at 14:41 -0400, Graham, Simon wrote:
> > I accept that this is not very nice and we should probably have a
> more
> > organized/documented way to do this but I'm not sure what would be
> > appropriate; any suggestions?
>
> A usespace tool to send such an ARP would be a very useful thing to
> have, if it doesn't already exist.
>
> The gratuitous arping in netfront is not very popular with the upstream
> Linux folks so this functionality is not in the paravirt_ops patches
> which are going upstream, so we'd need such a tool in the end anyway.
>
> Ian.
>
>
>
>


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel




--
best regards,
hanzhu

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel


 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.