Martin, Does IETF still have RFC editors who can help correcting English errors? I remember there one many years ago.
Other comments are inserted below: -----Original Message----- From: Martin Vigoureux <[email protected]> Sent: Thursday, November 19, 2020 9:42 AM To: Linda Dunbar <[email protected]>; [email protected]; [email protected]; [email protected] Subject: Re: AD review of draft-ietf-nvo3-vmm-16 Linda, please see in-line. Le 2020-11-17 à 20:38, Linda Dunbar a écrit : > Martin, > Thank you very much for finally squeezing time to review the draft, > after 2 years of WGLC and long journey of revisions to address Areas > Directorates comments. Being an AD is not easy, so many drafts to review.. > Replies to your comments are inserted below: > -----Original Message----- > From: Martin Vigoureux <[email protected]> > Sent: Monday, November 16, 2020 7:22 AM > To: [email protected]; [email protected]; [email protected] > Subject: AD review of draft-ietf-nvo3-vmm-16 Hi, I have several > concerns with this document. > There hasn't been a single response to the WG LC, which by the way > happened more than two years ago and the draft has undergone 13 > revisions since then. > [Linda] There have been a lot of comments during the Area Directorate > reviews, and private comments from NVO3 Chairs. Indeed, but that doesn't explain the silence at WG LC stage, and is in fact a strong incentive for running a new one, and in fact have a broader discussion about this draft. [Linda] Okay. > This document has an evident formatting issue (text width, section > titles, Status of This Memo, references, ...), as well as a reasonable > number of typos / unclear sentences making it quite hard to understand. > [Linda] Can you elaborate more on those issues? With English as a > second language, I am hoping to learn from the mistakes. NVO3 Chair > Matthews had a private session with us pointing English language > issues, we had revised draft to correct those issues. We would like to > learn moreI'm not a native english speaker/writer, but it is at least > easy to notice the formatting issue your document has. I can go through the document an pick the nits/typos and hard-to-parse sentences but that is not the core of the issue. [Linda] Since your time is much more valuable, is it easier for an RFC editor to help with the English? > It apparently aims at addressing Virtual Machine Mobility, but in fact > seems to only cover IP address preservation during such type of event. > This must be clarified. > [Linda] one of the big issues of VM Mobility in Layer 3 is when the > VMs need to maintain their original IP addresses after their move. If > VMs addresses can be re-assigned after their move, network becomes > very simple but applications running on the VMs can’t be moved freely. > Layer 2 addresses don’t have hierarchical structure as Layer 3 IP > addresses. All switches learn the host Layer 2 addresses on the fly > and time out the learned addresses in the Forwarding table when there > is no packets has the addresses in the SA/DST fields for certain period of > time. > That is why the draft is focusing on practices and actions when VMs > need to maintain their addresses after the move.I understood that. My > point is that this document should therefore not be called virtual machine mobility. [Linda] Is it better to call the draft "Solutions to preserve IP Addresses during VM mobility in Layer 2 and Layer 3 Networks"? > It is not clear to me what is specific to NVO3 networks in this document. > [Linda] The draft is to address the NVO3 Charter: > /The NVO3 WG will develop solutions for network virtualization based > on/ /the following architectural tenets:/ > /- Support for an IP-based underlay data plane/ That sort of confirms this is not NVO3 specific. [Linda] Do you suggest to go through independent RFC stream? > This document is said to describe solutions *commonly* used in data > centers. Also, it primarily only describes what needs to be done but > not how. > This makes me wonder what benefit does it bring to the community and > to operators of data centers. > [Linda] This document provides guidelines to DC operators if they want > to maintain VMs IP addresses during VM migration. Being able to move > VMs dynamically, from one server to another, makes it possible for > dynamic load balancing or work distribution. Therefore, dynamic VM > Mobility is highly desirable for large scale multi-tenant DCs possibly, but if those techniques are already in use, what is the benefit of having an RFC describing them? virtual machine mobility seems to be fairly well documented already and much more broadly than just about IP addressing preservation. It is also very challenging for the reader to determine whether all aspects of IP address preservation have been covered. [Linda] We have aimed to cover all aspects of IP address preservation. If we miss some aspects, can you elaborate? > This document refers to other specifications which themselves do not > provide the missing pieces e.g., RFC7666 does not describe how to > transfer VM states; [Linda] That is why we wrote this draft to > indicate that VMs states transferred are needed. But during the > numerous reviews, we had been advised to remote the actual protocols > of moving states and change the document to be “Informational” (from > Standard Track). I'm ok with that recommendation, because moving states has little to do with IP address preservation. The issue I point to is that you refer to RFC7666 for more information on moving states, but nothing in RFC7666 talks about that. > RFC8014 is not a specification for an NVE-to-NVA protocol. > [Linda] RFC8014 describes the NVE-to-NVA functions. indeed but your document doesn't say clearly which functions need to be activated and how is effectively used the protocol to achieve the desired objective. [Linda] Thank you for the specific action. we can add. > How section 7 relates to the rest of the document is unclear. It seems > to restate some elements described in 4.2 and 4.3 but not all. > [Linda] Section 4 is the Overview. Section 7 describes the details of > the Overview of Section 4. hmmm, then we can add this to the things that need to be clarified. Section 7 mas much less information than 4.2/4.3. In fact it is 42 lines long while 4.2+4.3 are 142 (and section 4, as a whole, 233). How can the overview be longer than the details? [Linda]Interesting point. Will ask the WG if more needs to be added or removed. > Section 8 and 9 seem to be out of the scope of this document. > [Linda] Section 8 and 9 describes what triggers the VMs move. It was > suggested from Aera Directorates review comments. In the intro you say that this document covers planned VM moves. Section 8 talks about other reasons for a move (failover, load, ...). This is confusing and in fact doesn't add anything to IP address preservations. Section 9 itself says that it is outside the scope of the document. [Linda] "failover, planned VM moves" are some of the reasons triggering the "VM Moving". > In its current state the document is not ready for review by the IESG > and I'm returning it to the WG. I encourage the WG to evaluate the > benefit of publishing this as an RFC, to discuss whether this should > be the product of NVO3 and would an alternate publication stream be > more appropriate. In any case this document needs more work. > [Linda] We are going around in circles. Not all drafts become RFCs and not all paths to RFC are straight. I'm not taking a decision here, I'm asking the WG to have a discussion. [Linda] sure. > -m _______________________________________________ nvo3 mailing list [email protected] https://www.ietf.org/mailman/listinfo/nvo3
