[virt-tools-list] virt-install --pxe REVISIT RESOLVED

[Daniel P. Berrange]

On Mon, Nov 15, 2010 at 11:01:57AM -0700, Phil Meyer wrote:
> On 11/12/2010 10:47 AM, Phil Meyer wrote:
> >Pleas guide me as to where and/or who would work this bug:
> >
> >Fedora 12+ and RHEL6 both suffer this issue.
> 
> 
> This was caused by the new seabios booting much faster than the old 
> BIOS.  Thus causing the dhcp request to run afoul of the 15 second 
> default delay in the 'new bridge' traffic.
> 
> By default, a new bridge on RHEL defaults to a 15 second delay before 
> any traffic can pass over the new bridge.
> 
> This is a 'convention' used to prevent bridge loops from causing network 
> meltdowns.
> 
> By setting the delay to 5 seconds, everything works perfectly.
> 
> To display the current setting:
> 
> # brctl showstp br0 | grep -i delay
>  forward delay            14.99                 bridge forward 
> delay      14.99
> 
> To set it:
> 
> # brctl setfd br0 5

In the libvirt networking docs we recommend using DELAY=0 to avoid this
problem. Even 5 seconds can be too long in some scenarios, and provided
you're not putting multiple physical NICs in one bridge, or attaching
a guest to multiple host networks, you'll be safe from loops

 http://wiki.libvirt.org/page/Networking#Creating_network_initscripts

Regards,
Daniel
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