On Thursday, April 14, 2011 at 5:04 PM, Kiran Yedavalli wrote: > Thanks Rajiv and Dan. Looks like we need metadata in any case for this to > work. We initially thought of this, but our platform does not support > metadata, so was wondering if there is a way without using metadata. Looks > like there is none. > > Also, what is the reason why Action Set does not support more than one action > of the same kind? One reason might be because there would be ambiguity when adding an action of whether you were overwriting or adding. Otherwise I think it's just for simplifying the spec.
Given that a hardware platform supports a particular action or parsing (for example, adding two MPLS tags at a time or matching IP after an MPLS tag) I think there will likely be vendor extensions that do these sorts of things for 1.1. -Dan > Thanks > Kiran > > From: Rajiv Ramanathan [mailto:[email protected]] > Sent: Thursday, April 14, 2011 1:58 PM > To: Kiran Yedavalli > Cc: [email protected] > Subject: Re: [openflow-discuss] Pushing 2 MPLS labels. > > A couple of solutions (variations of the same theme) are: > > Table 0: match on dest IP, set metadata > Table 1: match on input port, push inner label > Table 3: match on metadata, push outer label > > or > > Table 0: match on dest IP and input port, set metadata and push inner label > Table 1: match on metadata, push outer labe. > > > On Thu, Apr 14, 2011 at 10:37 AM, Kiran Yedavalli > <[email protected]> wrote: > > Hi, > > > > The problem is to push two MPLS labels onto a packet, the inner one based > > on input port and the outer one based on destination IP address. However, > > the spec does not allow this in any way. We looked at three options: > > > > Option 1. Match on input port on table 0 and push a MPLS label, next, match > > on dest IP address in table 1 and push a MPLS label. The spec does not > > allows this, because we cannot look at the IP address after we push a MPLS > > label, according to the spec. > > > > Option 2. Match on dest IP address on table 0 and push a MPLS label, next, > > match on input port in table 1 and push a MPLS label. But in this case, > > according to the spec, we can only push an outmost label everytime we push. > > This does not work for us either. > > > > Option 3. Accumlate all actions in the Action Set using the WriteActions > > Instruction. This does not work either, because the Action Set cannot have > > more than one of the same kind of action. > > > > Is there any other way of accomplishing this? If not, we think this is a > > flaw in the spec that does not allow for inserting more than one label. > > > > Thanks > > Kiran > > > > > > > > > > > > _______________________________________________ > > openflow-discuss mailing list > > [email protected] > > https://mailman.stanford.edu/mailman/listinfo/openflow-discuss > > _______________________________________________ > openflow-discuss mailing list > [email protected] > https://mailman.stanford.edu/mailman/listinfo/openflow-discuss > _______________________________________________ openflow-discuss mailing list [email protected] https://mailman.stanford.edu/mailman/listinfo/openflow-discuss
