2008/055 Solaris Bridging

[James Carlson]

Erik Nordmark writes:
> The VNIC abstraction makes it a lot more natural to expose the NICs 
> characteristics and capabilities (hardware checksum, LSO, etc) to the 
> domUs, than the current Linux approach of using a bridge to connect the 
> domUs to the NICs.

Right; I agree with that.  If that's the purpose of using bridges in
Xen/LDOMs, then real 802-type bridges aren't what you want, and the
VNIC abstraction is what you need.

If the purpose is just to create a separate OS instance to run the
bridging software (because you don't trust the daemons, perhaps), then
running this new feature in Xen or an LDOM makes more sense.

For what it's worth, this bridging project is about constructing
802-type bridges with Solaris, which means taking packets in one
physical interface and forwarding them out another.  It faces
"downward" towards the interfaces.

Other quasi-bridge-like things are out of scope, and many of them
(such as the cases you're citing where packets are "bridged" between
virtual nodes) are better handled by VNICs.  The sort of learning and
loop prevention mechanisms required for regular bridges don't apply
there.

-- 
James Carlson, Solaris Networking              <james.d.carlson at sun.com>
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