OPSAWG Working Group Balaji Venkat Venkataswami INTERNET-DRAFT Bhargav Bhikkaji Intended Status: Proposed Standard DELL-Force10 Expires: September 2012 March 26, 2012 VM to VTEP maps topology discovery in VXLAN based data centers draft-balaji-opsawg-vxlan-vm-topo-discovery-01 Abstract This document proposes a method by which in a VXLAN environment the ARP tables of each VTEP having an active VM belonging to a particular tenant where such active VMs are distributed amongst several VTEPs in a data center or across data centers are walked through and the collation of the location of such active VMs and the VTEPs they are located in is found for management and network resource planning purposes. Status of this Memo This Internet-Draft is submitted to IETF in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/1id-abstracts.html The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html Copyright and License Notice Copyright (c) 2012 IETF Trust and the persons identified as the document authors. All rights reserved. Balaji Venkat et.al, Expires September 2012 [Page 1] INTERNET DRAFT VM topology discovery in VXLAN March 2012 This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1 Terminology . . . . . . . . . . . . . . . . . . . . . . . . 3 1.2 Methodology . . . . . . . . . . . . . . . . . . . . . . . . 3 1.2.1 Algorithm . . . . . . . . . . . . . . . . . . . . . . . 6 2. Applicability to NMS Applications . . . . . . . . . . . . . . . 7 2.1 VTEP support . . . . . . . . . . . . . . . . . . . . . . . . 7 3 Security Considerations . . . . . . . . . . . . . . . . . . . . 8 4 IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 8 5 References . . . . . . . . . . . . . . . . . . . . . . . . . . 8 5.1 Normative References . . . . . . . . . . . . . . . . . . . 8 5.2 Informative References . . . . . . . . . . . . . . . . . . 8 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 8 Balaji Venkat et.al, Expires September 2012 [Page 2] INTERNET DRAFT VM topology discovery in VXLAN March 2012 1 Introduction It will be necessary in a VXLAN data center environment to locate the several active VMs belonging to one or more tenants or all tenants which are hosted by the VTEPs in the data center and list the active VMs such that management and network resource planning can be done for that tenant. This information may be useful to the network administrators of the data center deploying VXLAN and to the tenants that have their active VMs hosted in the data center running VXLAN for the mentioned purposes. 1.1 Terminology The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 [RFC2119]. 1.2 Methodology The following IP Address Translation table also called the ARP table as outlined in RFC 2011 will be useful in this method. It is possible that several IP sub-nets are deployed for a given tenant. For each such IP sub-net there may be a VLAN allocated. For routing between such IP sub-nets the default gateway for a VLAN that has its VNICs in several such VLANs may be deployed. In such a case the ARP tables of each of the interfaces of then active VM default gateway for the several VLANs involved is inspected to collate the different VLAN's active VMs that are hosted on the VTEPs in the VXLAN based data center. The algorithm that does this specific job of collation is explained in section 1.2.1. -- the IP Address Translation table -- The Address Translation tables contain the IpAddress to -- "physical" address equivalences. Some interfaces do not -- use translation tables for determining address -- equivalences (e.g., DDN-X.25 has an algorithmic method); -- if all interfaces are of this type, then the Address -- Translation table is empty, i.e., has zero entries. ipNetToMediaTable OBJECT-TYPE SYNTAX SEQUENCE OF IpNetToMediaEntry MAX-ACCESS not-accessible STATUS current Balaji Venkat et.al, Expires September 2012 [Page 3] INTERNET DRAFT VM topology discovery in VXLAN March 2012 DESCRIPTION "The IP Address Translation table used for mapping from IP addresses to physical addresses." ::= { ip 22 } ipNetToMediaEntry OBJECT-TYPE SYNTAX IpNetToMediaEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Each entry contains one IpAddress to `physical' address equivalence." INDEX { ipNetToMediaIfIndex, ipNetToMediaNetAddress } ::= { ipNetToMediaTable 1 } IpNetToMediaEntry ::= SEQUENCE { ipNetToMediaIfIndex INTEGER, ipNetToMediaPhysAddress PhysAddress, ipNetToMediaNetAddress IpAddress, ipNetToMediaType INTEGER } ipNetToMediaIfIndex OBJECT-TYPE SYNTAX INTEGER (1..2147483647) MAX-ACCESS read-create STATUS current DESCRIPTION "The interface on which this entry's equivalence is effective.The interface identified by a particular value of this index is the same interface as identified by the same value of RFC 1573's ifIndex." ::= { ipNetToMediaEntry 1 } ipNetToMediaPhysAddress OBJECT-TYPE SYNTAX PhysAddress MAX-ACCESS read-create STATUS current DESCRIPTION "The media-dependent `physical' address." ::= { ipNetToMediaEntry 2 } ipNetToMediaNetAddress OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-create STATUS current DESCRIPTION "The IpAddress corresponding to the media-dependent Balaji Venkat et.al, Expires September 2012 [Page 4] INTERNET DRAFT VM topology discovery in VXLAN March 2012 `physical' address." ::= { ipNetToMediaEntry 3 } ipNetToMediaType OBJECT-TYPE SYNTAX INTEGER { other(1), -- none of the following invalid(2), -- an invalidated mapping dynamic(3), static(4) } MAX-ACCESS read-create STATUS current DESCRIPTION "The type of mapping. Setting this object to the value invalid(2) has the effect of invalidating the corresponding entry in the ipNetToMediaTable. That is, it effectively disassociates the interface identified with said entry from the mapping identified with said entry. It is an implementation- specific matter as to whether the agent removes an invalidated entry from the table.Accordingly, management stations must be prepared to receive tabular information from agents that corresponds to entries not currently in use. Proper interpretation of such entries requires examination of the relevant ipNetToMediaType object." ::= { ipNetToMediaEntry 4 } Balaji Venkat et.al, Expires September 2012 [Page 5] INTERNET DRAFT VM topology discovery in VXLAN March 2012 1.2.1 Algorithm Input : Seed VTEP IP address of a particular tenant Y Output: Collated output of all active VMs in the respective VTEPs in the VXLAN data center. AlgorithmBegin While more VTEPs to be scanned START_LABEL: While ( there exists more entries in current_vlan ARP TABLE Where the TABLE = RFC 2011 ipNetToMediaEntryTable of Seed VTEP ) Get Next of the entry in the ARP table of the VTEP; If (active VM listed in ARP table is tenant of Y ) then Add to list the unique ARP table entry; Add VTEP in the ARP table entry to unique VTEP list; endif EndWhile If (any other VLAN's ARP table is available in case the VM is a gateway VM) then Set current_vlan = VLAN located; goto START_LABEL; else // do nothing; endif Set Seed VTEP = Next VTEP address in the unique VTEP list; Advance one entry in the unique VTEP list; Set NextVTEP = Seed VTEP; EndWhile; AlgorithmEnd; Balaji Venkat et.al, Expires September 2012 [Page 6] INTERNET DRAFT VM topology discovery in VXLAN March 2012 2. Applicability to NMS Applications Network Management Applications can provide a friendly user interface where the topology of the Layer 3 transport network with the TORs and respective VTEPs under them can be discovered using regular Layer 3 topology discovery. The algorithm in 1.2.1 can then be executed and the active VMs of various tenants displayed. This will help in management and in network resource planning. 2.1 VTEP support VTEPs in the VXLAN environment in data centers are expected to have SNMP support in the form of MIBs as per [2011]. Balaji Venkat et.al, Expires September 2012 [Page 7] INTERNET DRAFT VM topology discovery in VXLAN March 2012 3 Security Considerations The usual SNMP related security concerns apply. 4 IANA Considerations None. 5 References 5.1 Normative References [KEYWORDS] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC1776] Crocker, S., "The Address is the Message", RFC 1776, April 1 1995. [TRUTHS] Callon, R., "The Twelve Networking Truths", RFC 1925, April 1 1996. 5.2 Informative References [RFC2011] McCloghrie, K., Ed., "SNMPv2 Management Information Base for the Internet Protocol using SMIv2", RFC 2011, November 1996. [EVILBIT] Bellovin, S., "The Security Flag in the IPv4 Header", RFC 3514, April 1 2003. [RFC5513] Farrel, A., "IANA Considerations for Three Letter Acronyms", RFC 5513, April 1 2009. [RFC5514] Vyncke, E., "IPv6 over Social Networks", RFC 5514, April 1 2009. Authors' Addresses Balaji Venkat Venkataswami, Dell-Force10, Olympia Technology Park, Fortius block, 7th & 8th Floor, Plot No. 1, SIDCO Industrial Estate, Balaji Venkat et.al, Expires September 2012 [Page 8] INTERNET DRAFT VM topology discovery in VXLAN March 2012 Guindy, Chennai - 600032. TamilNadu, India. Tel: +91 (0) 44 4220 8400 Fax: +91 (0) 44 2836 2446 EMail: BALAJI_VENKAT_VENKAT@dell.com Bhargav Bhikkaji, Dell-Force10, 350 Holger Way, San Jose, CA U.S.A Email: Bhargav_Bhikkaji@dell.com Balaji Venkat et.al, Expires September 2012 [Page 9]