[libvirt] --checksum-fill error on Ubuntu 10.04

Osier jyang at redhat.com
Tue Oct 26 02:41:25 UTC 2010


caused by network filter driver depends on the newer iptables,
there is no "--checksum-fill" option indeed in older iptables.

The following commit log is from iptables git.

commit 9d1b11102b53103c00b7fddf4658a4d2bdee1338
Author: Michael S. Tsirkin <mst at redhat.com>
Date:   Thu Jul 15 17:23:24 2010 +0200

    extensions: libxt_CHECKSUM extension
    
    This adds a `CHECKSUM' target, which can be used in the iptables mangle
    table.
    
    You can use this target to compute and fill in the checksum in
    a packet that lacks a checksum.  This is particularly useful,
    if you need to work around old applications such as dhcp clients,
    that do not work well with checksum offloads, but don't want to disable
    checksum offload in your device.
    
    The problem happens in the field with virtualized applications.
    For reference, see Red Hat bz 605555, as well as
    http://www.spinics.net/lists/kvm/msg37660.html
    
    Typical expected use (helps old dhclient binary running in a VM):
    iptables -A POSTROUTING -t mangle -p udp --dport bootpc \
    -j CHECKSUM --checksum-fill
    
    Includes fixes by Jan Engelhardt <jengelh at medozas.de>
    Signed-off-by: Michael S. Tsirkin <mst at redhat.com>
    Signed-off-by: Patrick McHardy <kaber at trash.net>


Even on my FC13, it's without "CHECKSUM" support, the build date is 
'Thu 08 Apr 2010 06:30:45 PM CST', :-)

Could we treat the error message as warnings? or make it only works for newer 
iptables?

- Osier

----- "Justin Clift" <jclift at redhat.com> wrote:

> Hi us,
> 
> Just noticed an error message when manually starting libvirtd (built
> from git) on Ubuntu 10.04, while checking something else:
> 
>   iptables v1.4.4: unknown option `--checksum-fill'
> 
> It shows up in the initial default network setup:
> 
>   10:40:19.807: error : virRunWithHook:855 : internal error
> '/sbin/iptables --table mangle --insert POSTROUTING --out-interface
> virbr0 --protocol udp --destination-port 68 --jump CHECKSUM
> --checksum-fill' exited with non-zero status 2 and signal 0: iptables
> v1.4.4: unknown option `--checksum-fill'
> Try `iptables -h' or 'iptables --help' for more information.
> 
> Just a FYI, in case someone wants to look into it.
> 
> Regards and best wishes,
> 
> Justin Clift
> 
> --
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