[FEATURE REQUEST] - change Bridge Forwarding Delay value

[johnodon]

I was having a hard time getting a KVM VM to boot from PXE (DHCP timeout).  So I researched and found this:  https://bugzilla.redhat.com/show_bug.cgi?id=586324

 

More info can be found here:  http://www.linuxfoundation.org/collaborate/workgroups/networking/bridge

 

Forwarding delay

 

Forwarding delay time is the time spent in each of the Listening and Learning states before the Forwarding state is entered. This delay is so that when a new bridge comes onto a busy network it looks at some traffic before participating.

 

#  brctl setfd bridgename time

 

I ran the following command in an unraid terminal and I was able to boot my PXE image in a VM:

 

brctl setfd br0 4.0

 

Reading a little further in the bug report, the consensus seems to be that the value of the bridge forwarding delay should be set to 0 in virt environments.  I can easily do this in the GO file but can this be changed in the core so I don't have to?  Or maybe have a place to set the value on the Network settings page?

 

Thanks,

 

John

[jonp]

Very thorough feature request.  Thanks.  Have forwarded to Eric for review.

[limetech]

Interesting.  When we changed the network startup script to wait in-line (up to 60 sec) for a dhcp lease, I almost added a 'brctl setfd br0 0' to the default initialization for the root bridge, but I wasn't sure about how that would affect down-link virtual bridges.  Replies in the redhat bug report you found seem to imply setting fwd delay to 0 is ok.  I think what we'll do is add this as a configurable setting on the Network Page.

[johnodon]

Awesome!

 

Thanks Lt!

 

John