On Aug 3, 2005, at 5:34 PM, Ben Greear wrote: > John T. Kamenik wrote: > >> On Aug 3, 2005, at 4:58 PM, Ben Greear wrote: >> >>> John T. Kamenik wrote: >>> >>> >>>> I have a linux based bridge/router. On one side is a VLAN >>>> network, and on the other an Ethernet network. The VLAN >>>> network uses the user_priority field in the VLAN header to >>>> perform various forms of QoS. The ethernet network does a >>>> similar thing with the IP ToS bits. Is there an easy way to >>>> map the ToS bits to user_priority and visa versa? And the >>>> solution cannot be "use a Cisco" :). >>>> >>>> >>> >>> I'm sure the linux iptables code can somehow do the translation >>> for you...but I don't know the exact details... >>> >>> >> Iptables is what I thought about using first. However, iptables >> does not have an understanding of VLANs. At least not to my >> knowledge. This means that iptables has no knowledge of the >> user_priority field and therefore cannot map to or from it. >> > > Get VLAN to map .1q to skb->priority, and get ip tables to map skb- > >priority > to ToS. (and vice versa). > > Ben I couldn't find how IP tables could map to/from skb->priority. Is that what Marking a packet does, or is there something more obvious that I am just not seeing? Also, will changing the skb-priority screw-up the rudimentary QoS that Linux uses it for? John
