Santosh, But your draft says:
" BFD session can be used to run between VM's for VM's connectivity check:" So, which one is it? VTEP-to-VTEP or VM- to-VM? Also what is the MAC-DA of inner Ethernet header? Thx Shahram -----Original Message----- From: Santosh P K [mailto:[email protected]] Sent: Tuesday, June 30, 2015 2:13 AM To: Shahram Davari; Gregory Mirsky; Vengada Prasad Govindan (venggovi) Cc: [email protected] Subject: RE: New Version Notification for draft-spallagatti-bfd-vxlan-00.txt > Another question I have is how do you forward these BFD packets from VTEP > to VM? Since DIP = 127/8, I assume there is no way to forward such packets > past the VTEP. We don't want to send it past VTEP as BFD will terminate at VTEP itself. Right now use of 127/8 is not really clear as inner IP address. We have again added some text for inner IP address and its use. > > If you want to do VM to VM connectivity check then I suggest one of the > following: > > 1) if VMs are only L2 aware and VXLAN is L2VPN, the run Ethernet OAM > between VMs > 2) If VMs are L2 and L3 aware and VXLAN is L2VPN then run BFD over IP/UDP > over Ethernet over VXLAN > 3) If VMs are L3 aware and VXLAN is L3VPN then you have 2 cases: > 3a) If VTEP and VMs are physically in the same CPU core then run > what > you are proposing in this draft (1-hop BFD). Although it should give you same > result as running BFD over the outer IP tunnel > 3b) If VTEP and VMs are physically separate (such as VTEP is in TOR > and > VM is CPU core), then run something similar to what you are proposing but > with Multi-hop DIP address so that BFD can be forwarded to VM from VTEP. > We are not trying to address VM to VM connectivity check as I believe that does not really need any changes and BFD as it is should run. Proposal is from VTEP to VTEP. Thanks Santosh P K > -----Original Message----- > From: Rtg-bfd [mailto:[email protected]] On Behalf Of Shahram > Davari > Sent: Monday, June 29, 2015 4:15 PM > To: Gregory Mirsky; Vengada Prasad Govindan (venggovi) > Cc: [email protected] > Subject: RE: New Version Notification for draft-spallagatti-bfd-vxlan-00.txt > > Hi Greg, > > I don't see much value in running BFD for SS-PW compared to running BFD > over the LSP. > > Thx > SD > > -----Original Message----- > From: Gregory Mirsky [mailto:[email protected]] > Sent: Monday, June 29, 2015 2:21 PM > To: Shahram Davari; Vengada Prasad Govindan (venggovi) > Cc: MALLIK MUDIGONDA (mmudigon); Santosh P K; [email protected] > Subject: RE: New Version Notification for draft-spallagatti-bfd-vxlan-00.txt > > Hi Shahram, > I'll get to VXLAN shorty but wanted to ask quick question about SS-PW. True, > we have case of MS-PW where PW label used (that was discussed in MPLS- > TP in particular). But that doesn't mean that VCCV BFD has value only for MS- > PW and for SS-PW has no value. Would you agree? > > Regards, > Greg > > -----Original Message----- > From: Shahram Davari [mailto:[email protected]] > Sent: Monday, June 29, 2015 2:02 PM > To: Gregory Mirsky; Vengada Prasad Govindan (venggovi) > Cc: MALLIK MUDIGONDA (mmudigon); Santosh P K; [email protected] > Subject: RE: New Version Notification for draft-spallagatti-bfd-vxlan-00.txt > > Hi Greg, > > You are welcome. Could you please clarify which one of the following is the > packet format: > > 1) OuterL2-Outer IP-UDP-VXLAN-Inner L2-Inner IP-UDP-BFD > > Or > > 2) OuterL2-Outer IP-UDP-VXLAN-Inner IP-UDP-BFD > > If (2) hen how do you specify the VXLAN payload in IP and not Ethernet? > > Also This is different from PW BFD, since in case of PW, there can be MS-PW, > where the LSP BFD is not end-to-end. But in this case we don't have MS- > VXLAN. > So the span of the VXLAN and the IP tunnel is the same. > > In other words you have to specify in which part of forwarding the BFD the > VXLAN Tag is used. If it is not used then it has no effect. > > Thx > Shahram > > -----Original Message----- > From: Gregory Mirsky [mailto:[email protected]] > Sent: Monday, June 29, 2015 1:51 PM > To: Shahram Davari; Vengada Prasad Govindan (venggovi) > Cc: MALLIK MUDIGONDA (mmudigon); Santosh P K; [email protected] > Subject: RE: New Version Notification for draft-spallagatti-bfd-vxlan-00.txt > > Hi Shahram, > thank you for your comments to this proposal that make the discussion so > much alive. > I think that processing of the VXLAN tag by VTEP before validating BFD is > sufficient, in my view, level of verification. In VCCV BFD the PW label is not > used for BFD forwarding but we find it useful as Service OAM in addition to > RFC 5884, BFD over MPLS LSP. > > Regards, > Greg > > -----Original Message----- > From: Shahram Davari [mailto:[email protected]] > Sent: Monday, June 29, 2015 10:39 AM > To: Vengada Prasad Govindan (venggovi) > Cc: Gregory Mirsky; MALLIK MUDIGONDA (mmudigon); Santosh P K; rtg- > [email protected] > Subject: RE: New Version Notification for draft-spallagatti-bfd-vxlan-00.txt > > Hi Prasad, > > Is this a special type of BFD or standard BFD RFC 5880 and 5881)? Since > standard BFD processing does no care where the BFD came from it only looks > at "your discriminator" to update BFD state machine. > > Also I don't see how many VXLANs can be checked via a single BFD session. > Could you please describe? > > Lastly checking to see a VXLAN/VNI forwarding domain exist in a VTEP should > not require BFD. Just use some query mechanism. Why do you need to run > continuous BFD. > > What you have to show me to convince me that your draft solves a real > problem is to show that VXLAN tag is used for BFD forwarding. Otherwise > BFD over the outer or Inner IP should give you all coverage needed. > > > Thx > Shahram > > > > > -----Original Message----- > From: Vengada Prasad Govindan (venggovi) [mailto:[email protected]] > Sent: Monday, June 29, 2015 3:11 AM > To: Shahram Davari > Cc: Gregory Mirsky; MALLIK MUDIGONDA (mmudigon); Santosh P K; rtg- > [email protected] > Subject: RE: New Version Notification for draft-spallagatti-bfd-vxlan-00.txt > > Hello Shahram, > At the terminating VTEP, VxLAN information is used to consume the BFD > packet. In other words, a BFD session increases the confidence of the > existence of the VNI-Forwarding Domain mapping and the presence of valid > VTEP termination configuration at the terminating VTEP. At the originating > VTEP, it is a matter of implementation of how many VxLAN tables are > exercised in the datapath (am aware of at least one implementation where it > is being exercised to a considerable extent). > > Thanks > Prasad > > -----Original Message----- > From: Shahram Davari [mailto:[email protected]] > Sent: Saturday, June 27, 2015 8:24 PM > To: Shahram Davari > Cc: Vengada Prasad Govindan (venggovi); Gregory Mirsky; MALLIK > MUDIGONDA (mmudigon); Santosh P K; [email protected] > Subject: Re: New Version Notification for draft-spallagatti-bfd-vxlan-00.txt > > Hi > > May be a better way to make this clear is to answer the following question: > > Where is the VXLAN tag information used in this BFD forwarding? > > Thx > Shahram
