#660882 pv network device does not support multicast

Package:
src:xen
Source:
xen
Submitter:
Simon Hobson
Date:
2014-11-24 16:15:08 UTC
Severity:
wishlist
#660882#5
Date:
2012-02-22 16:01:49 UTC
From:
To:
Severity: normal

See also, bug 660768
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=660768


atalkd appears to be unable to open virtual network interfaces when
run in a Xen PV guest.

With nothing set in atalkd.conf, it reports :
   eth0: disabled.
   atalkd: zero interfaces, exiting.

Adding "eth0" to atalkd.conf results in :
   eth0: Invalid argument
   Can't configure multicast.
   eth0: disabled.
   atalkd: zero interfaces, exiting.


If the entire VM is moved to a physical host (ie running native with
no virtualisation), then atalkd works as expected. This physical
machine has a GeForce chipset and the forcedeth network driver. the
only changes were to use eth1 instead of eth0, and make the system
bootable with GRUB.

Suggestion from netatalk maintainer is that atalkd requires multicast
support - but this is not provided by Xen virtual NIC/driver.



For the Xen host :

Debian: Squeeze

Kernel :
Linux serge 2.6.32-5-xen-amd64 #1 SMP Mon Jan 16 20:48:30 UTC 2012
x86_64 GNU/Linux

LibC6: 2.11.3-2

libxenstore3.0           4.0.1-4
xen-hypervisor-4.0-amd64 4.0.1-4
xen-utils-4.0            4.0.1-4
xen-utils-common         4.0.0-1
xenstore-utils           4.0.1-4



For the guest (DomU)

Debian: Squeeze

Kernel :
Linux newpatsy 2.6.32-5-xen-amd64 #1 SMP Mon Jan 16 20:48:30 UTC 2012
x86_64 GNU/Linux

LibC6: 2.11.3-2
#660882#10
Date:
2012-03-08 14:40:41 UTC
From:
To:
I have now built a test host with Wheezy & Xen 4.1. With the same
Squeeze guest, the problem persists.

Host is now :
Debian Wheezy

Kernel :
Linux saffy 3.2.0-1-amd64 #1 SMP Fri Feb 17 05:17:36 UTC 2012 x86_64 GNU/Linux

libc6: 2.13-27


libxen-4.1               4.1.2-2
libxenstore3.0           4.1.2-2
xen-hypervisor-4.1-amd64 4.1.2-2
xen-tools                4.2.1-1
xen-utils-4.1            4.1.2-2
xen-utils-common         4.1.2-1
xenstore-utils           4.1.2-2
#660882#15
Date:
2012-03-08 15:49:57 UTC
From:
To:
Further update.
I've upgraded the client to Wheezy as well (same kernel and libc6 as
host). Still no change.
#660882#20
Date:
2012-07-10 18:07:33 UTC
From:
To:
tags 660882 +upstream
severity 660882 wishlist
retitle 660882 pv network device does not support multicast
thanks

Hi Simon,

I'm afraid the Xen PV drivers (on Linux at least) do not support
multicast.

There has historically been some support for multicast, IIRC the old
Solaris front and backends did support it so there is some support
defined but not implemented. e.g. see xen/include/public/io/netif.h and
the XEN_NETIF_EXTRA_TYPE_MCAST_{ADD,DEL} message types but these are not
implemented in the Linux front/backends.

If you want this fixed I think your best bet would be to engage with the
upstream project on xen-devel@lists.xen.org (and perhaps
netdev@vger.kernel.org too). I'm afraid this is more than likely going
to mean scratching your own itch and implementing the required support.

Probably not the answer you were looking for, sorry.

Ian.
#660882#29
Date:
2012-07-10 18:07:33 UTC
From:
To:
tags 660882 +upstream
severity 660882 wishlist
retitle 660882 pv network device does not support multicast
thanks

Hi Simon,

I'm afraid the Xen PV drivers (on Linux at least) do not support
multicast.

There has historically been some support for multicast, IIRC the old
Solaris front and backends did support it so there is some support
defined but not implemented. e.g. see xen/include/public/io/netif.h and
the XEN_NETIF_EXTRA_TYPE_MCAST_{ADD,DEL} message types but these are not
implemented in the Linux front/backends.

If you want this fixed I think your best bet would be to engage with the
upstream project on xen-devel@lists.xen.org (and perhaps
netdev@vger.kernel.org too). I'm afraid this is more than likely going
to mean scratching your own itch and implementing the required support.

Probably not the answer you were looking for, sorry.

Ian.