Hi,
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.
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.
I think this draft covers just (3a) and in such case it is pretty much
equivalent of running BFD over the outer IP tunnel, since the span of both BFDs
are the same and VXLAN is not used for forwarding for BFD processing.
Thx
Shahram
Thx
Shahram
-----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; [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; [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
