idnits 2.17.1 draft-ietf-nvo3-hpvr2nve-cp-req-14.txt: Checking boilerplate required by RFC 5378 and the IETF Trust (see https://trustee.ietf.org/license-info): ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt: ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/checklist : ---------------------------------------------------------------------------- No issues found here. Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year -- The document date (February 8, 2018) is 2262 days in the past. Is this intentional? Checking references for intended status: Informational ---------------------------------------------------------------------------- == Missing Reference: 'RFC2119' is mentioned on line 182, but not defined Summary: 0 errors (**), 0 flaws (~~), 2 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 NVO3 Working Group Y. Li 3 INTERNET-DRAFT D. Eastlake 4 Intended Status: Informational Huawei Technologies 5 L. Kreeger 6 Arrcus, Inc 7 T. Narten 8 IBM 9 D. Black 10 Dell EMC 11 Expires: August 12, 2018 February 8, 2018 13 Split Network Virtualization Edge (Split-NVE) Control Plane Requirements 14 draft-ietf-nvo3-hpvr2nve-cp-req-14 16 Abstract 18 In a Split Network Virtualization Edge (Split-NVE) architecture, the 19 functions of the NVE (Network Virtualization Edge) are split across a 20 server and an external network equipment which is called an external 21 NVE. The server-resident control plane functionality resides in 22 control software, which may be part of hypervisor or container 23 management software; for simplicity, this document refers to the 24 hypervisor as the location of this software. 26 Control plane protocol(s) between a hypervisor and its associated 27 external NVE(s) are used by the hypervisor to distribute its virtual 28 machine networking state to the external NVE(s) for further handling. 29 This document illustrates the functionality required by this type of 30 control plane signaling protocol and outlines the high level 31 requirements. Virtual machine states as well as state transitioning 32 are summarized to help clarify the protocol requirements. 34 Status of this Memo 36 This Internet-Draft is submitted to IETF in full conformance with the 37 provisions of BCP 78 and BCP 79. 39 Internet-Drafts are working documents of the Internet Engineering 40 Task Force (IETF), its areas, and its working groups. Note that 41 other groups may also distribute working documents as 42 Internet-Drafts. 44 Internet-Drafts are draft documents valid for a maximum of six months 45 and may be updated, replaced, or obsoleted by other documents at any 46 time. It is inappropriate to use Internet-Drafts as reference 47 material or to cite them other than as "work in progress." 49 The list of current Internet-Drafts can be accessed at 50 http://www.ietf.org/1id-abstracts.html 52 The list of Internet-Draft Shadow Directories can be accessed at 53 http://www.ietf.org/shadow.html 55 Copyright and License Notice 57 Copyright (c) 2018 IETF Trust and the persons identified as the 58 document authors. All rights reserved. 60 This document is subject to BCP 78 and the IETF Trust's Legal 61 Provisions Relating to IETF Documents 62 (http://trustee.ietf.org/license-info) in effect on the date of 63 publication of this document. Please review these documents 64 carefully, as they describe your rights and restrictions with respect 65 to this document. Code Components extracted from this document must 66 include Simplified BSD License text as described in Section 4.e of 67 the Trust Legal Provisions and are provided without warranty as 68 described in the Simplified BSD License. 70 Table of Contents 72 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 73 1.1 Terminology . . . . . . . . . . . . . . . . . . . . . . . . 5 74 1.2 Target Scenarios . . . . . . . . . . . . . . . . . . . . . 6 75 2. VM Lifecycle . . . . . . . . . . . . . . . . . . . . . . . . . 8 76 2.1 VM Creation Event . . . . . . . . . . . . . . . . . . . . . 8 77 2.2 VM Live Migration Event . . . . . . . . . . . . . . . . . . 9 78 2.3 VM Termination Event . . . . . . . . . . . . . . . . . . . . 10 79 2.4 VM Pause, Suspension and Resumption Events . . . . . . . . . 10 80 3. Hypervisor-to-NVE Control Plane Protocol Functionality . . . . 10 81 3.1 VN Connect and Disconnect . . . . . . . . . . . . . . . . . 11 82 3.2 TSI Associate and Activate . . . . . . . . . . . . . . . . . 12 83 3.3 TSI Disassociate and Deactivate . . . . . . . . . . . . . . 15 84 4. Hypervisor-to-NVE Control Plane Protocol Requirements . . . . . 16 85 5. VDP Applicability and Enhancement Needs . . . . . . . . . . . . 17 86 6. Security Considerations . . . . . . . . . . . . . . . . . . . . 19 87 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 19 88 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 19 89 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 20 90 8.1 Normative References . . . . . . . . . . . . . . . . . . . 20 91 8.2 Informative References . . . . . . . . . . . . . . . . . . 20 92 Appendix A. IEEE 802.1Q VDP Illustration (For information only) . 20 93 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 23 95 1. Introduction 97 In the Split-NVE architecture shown in Figure 1, the functionality of 98 the NVE (Network Virtualization Edge) is split across an end device 99 supporting virtualization and an external network device which is 100 called an external NVE. The portion of the NVE functionality located 101 on the end device is called the tNVE and the portion located on the 102 external NVE is called the nNVE in this document. Overlay 103 encapsulation/decapsulation functions are normally off-loaded to the 104 nNVE on the external NVE. 106 The tNVE is normally implemented as a part of hypervisor or container 107 and/or virtual switch in an virtualized end device. This document 108 uses the term "hypervisor" throughout when describing the Split-NVE 109 scenario where part of the NVE functionality is off-loaded to a 110 separate device from the "hypervisor" that contains a VM (Virtual 111 Machine) connected to a VN (Virutal Network). In this context, the 112 term "hypervisor" is meant to cover any device type where part of the 113 NVE functionality is off-loaded in this fashion, e.g.,a Network 114 Service Appliance or Linux Container. 116 The NVO3 problem statement [RFC7364], discusses the needs for a 117 control plane protocol (or protocols) to populate each NVE with the 118 state needed to perform the required functions. In one scenario, an 119 NVE provides overlay encapsulation/decapsulation packet forwarding 120 services to Tenant Systems (TSs) that are co-resident within the NVE 121 on the same End Device (e.g. when the NVE is embedded within a 122 hypervisor or a Network Service Appliance). In such cases, there is 123 no need for a standardized protocol between the hypervisor and NVE, 124 as the interaction is implemented via software on a single device. 125 While in the Split-NVE architecture scenarios, as shown in figure 2 126 to figure 4, control plane protocol(s) between a hypervisor and its 127 associated external NVE(s) are required for the hypervisor to 128 distribute the virtual machines networking states to the NVE(s) for 129 further handling. The protocol is an NVE-internal protocol and runs 130 between tNVE and nNVE logical entities. This protocol is mentioned in 131 the NVO3 problem statement [RFC7364] and appears as the third work 132 item. 134 Virtual machine states and state transitioning are summarized in this 135 document showing events where the NVE needs to take specific actions. 136 Such events might correspond to actions the control plane signaling 137 protocol(s) need to take between tNVE and nNVE in the Split-NVE 138 scenario. The high level requirements to be fulfilled are stated. 140 +------------ Split-NVE -----------+ 141 | | 142 | | 143 +---------------|-----+ | 144 | +-------------|----+| | 145 | | +--+ +---\|/--+|| +------|--------------+ 146 | | |VM|---+ ||| | \|/ | 147 | | +--+ | ||| |+--------+ | 148 | | +--+ | tNVE |||---------------------|| | | 149 | | |VM|---+ ||| || nNVE | | 150 | | +--+ +--------+|| || | | 151 | | || |+--------+ | 152 | +--Hypervisor------+| +---------------------+ 153 +---------------------+ 155 End Device External NVE 157 Figure 1 Split-NVE structure 159 This document uses VMs as an example of Tenant Systems (TSs) in order 160 to describe the requirements, even though a VM is just one type of 161 Tenant System that may connect to a VN. For example, a service 162 instance within a Network Service Appliance is another type of TS, as 163 are systems running on an OS-level virtualization technologies like 164 containers. The fact that VMs have lifecycles (e.g., can be created 165 and destroyed, can be moved, and can be started or stopped) results 166 in a general set of protocol requirements, most of which are 167 applicable to other forms of TSs although not all of the requirements 168 are applicable to all forms of TSs. 170 Section 2 describes VM states and state transitioning in the VM's 171 lifecycle. Section 3 introduces Hypervisor-to-NVE control plane 172 protocol functionality derived from VM operations and network events. 173 Section 4 outlines the requirements of the control plane protocol to 174 achieve the required functionality. 176 1.1 Terminology 178 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 179 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 180 document are to be interpreted as described in RFC 2119 [RFC2119] and 181 RFC 8174 [RFC8174]. 183 This document uses the same terminology as found in [RFC7365]. This 184 section defines additional terminology used by this document. 186 Split-NVE: a type of NVE (Network Virtualization Edge) where the 187 functionalities are split across an end device supporting 188 virtualization and an external network device. 190 tNVE: the portion of Split-NVE functionalities located on the end 191 device supporting virtualization. It interacts with a tenant system 192 through an internal interface in the end device. 194 nNVE: the portion of Split-NVE functionalities located on the network 195 device that is directly or indirectly connected to the end device 196 holding the corresponding tNVE. nNVE normally performs encapsulation 197 to and decapsulation from the overlay network. 199 External NVE: the physical network device holding the nNVE 201 Hypervisor: the logical collection of software, firmware and/or 202 hardware that allows the creation and running of server or service 203 appliance virtualization. tNVE is located under a Hypervisor. 204 Hypervisor is loosely used in this document to refer to the end 205 device supporting the virtualization. For simplicity, we also use 206 Hypervisor to represent both hypervisor and container. 208 Container: Please refer to Hypervisor. For simplicity this document 209 use the term hypervisor to represent both hypervisor and container. 211 VN Profile: Meta data associated with a VN (Virtual Network) that is 212 applied to any attachment point to the VN. That is, VAP (Virtual 213 Access Point) properties that are applied to all VAPs associated with 214 a given VN and used by an NVE when ingressing/egressing packets 215 to/from a specific VN. Meta data could include such information as 216 ACLs, QoS settings, etc. The VN Profile contains parameters that 217 apply to the VN as a whole. Control protocols between the NVE and 218 NVA (Network Virtualization Authority) could use the VN ID or VN Name 219 to obtain the VN Profile. 221 VSI: Virtual Station Interface. [IEEE 802.1Q] 223 VDP: VSI Discovery and Configuration Protocol [IEEE 802.1Q] 225 1.2 Target Scenarios 227 In the Split-NVE architecture, an external NVE can provide an offload 228 of the encapsulation / decapsulation functions and network policy 229 enforcement as well as the VN Overlay protocol overhead. This 230 offloading may improve performance and/or save resources in the End 231 Device (e.g. hypervisor) using the external NVE. 233 The following figures give example scenarios of a Split-NVE 234 architecture. 236 Hypervisor Access Switch 237 +------------------+ +-----+-------+ 238 | +--+ +-------+ | | | | 239 | |VM|---| | | VLAN | | | 240 | +--+ | tNVE |---------+ nNVE| +--- Underlying 241 | +--+ | | | Trunk | | | Network 242 | |VM|---| | | | | | 243 | +--+ +-------+ | | | | 244 +------------------+ +-----+-------+ 245 Figure 2 Hypervisor with an External NVE 247 Hypervisor L2 Switch 248 +---------------+ +-----+ +----+---+ 249 | +--+ +----+ | | | | | | 250 | |VM|---| | |VLAN | |VLAN | | | 251 | +--+ |tNVE|-------+ +-----+nNVE| +--- Underlying 252 | +--+ | | |Trunk| |Trunk| | | Network 253 | |VM|---| | | | | | | | 254 | +--+ +----+ | | | | | | 255 +---------------+ +-----+ +----+---+ 256 Figure 3 Hypervisor with an External NVE 257 connected through an Ethernet Access Switch 259 Network Service Appliance Access Switch 260 +--------------------------+ +-----+-------+ 261 | +------------+ | \ | | | | 262 | |Net Service |----| \ | | | | 263 | |Instance | | \ | VLAN | | | 264 | +------------+ |tNVE| |------+nNVE | +--- Underlying 265 | +------------+ | | | Trunk| | | Network 266 | |Net Service |----| / | | | | 267 | |Instance | | / | | | | 268 | +------------+ | / | | | | 269 +--------------------------+ +-----+-------+ 270 Figure 4 Physical Network Service Appliance with an External NVE 272 Tenant Systems connect to external NVEs via a Tenant System Interface 273 (TSI). The TSI logically connects to the external NVE via a Virtual 274 Access Point (VAP) [RFC8014]. The external NVE may provide Layer 2 or 275 Layer 3 forwarding. In the Split-NVE architecture, the external NVE 276 may be able to reach multiple MAC and IP addresses via a TSI. An IP 277 address can be in either IPv4 or IPv6 format. For example, Tenant 278 Systems that are providing network services (such as transparent 279 firewall, load balancer, or VPN gateway) are likely to have a complex 280 address hierarchy. This implies that if a given TSI disassociates 281 from one VN, all the MAC and/or IP addresses are also disassociated. 282 There is no need to signal the deletion of every MAC or IP when the 283 TSI is brought down or deleted. In the majority of cases, a VM will 284 be acting as a simple host that will have a single TSI and single MAC 285 and IP visible to the external NVE. 287 Figures 2 through 4 show the use of VLANs to separate traffic for 288 multiple VNs between the tNVE and nNVE; VLANs are not strictly 289 necessary if only one VN is involved, but multiple VNs are expected 290 in most cases. Hence this draft assumes the presence of VLANs. 292 2. VM Lifecycle 294 Figure 2 of [RFC7666] shows the state transition of a VM. Some of the 295 VM states are of interest to the external NVE. This section 296 illustrates the relevant phases and events in the VM lifecycle. Note 297 that the following subsections do not give an exhaustive traversal of 298 VM lifecycle state. They are intended as the illustrative examples 299 which are relevant to Split-NVE architecture, not as prescriptive 300 text; the goal is to capture sufficient detail to set a context for 301 the signaling protocol functionality and requirements described in 302 the following sections. 304 2.1 VM Creation Event 306 The VM creation event causes the VM state transition from Preparing 307 to Shutdown and then to Running [RFC7666]. The end device allocates 308 and initializes local virtual resources like storage in the VM 309 Preparing state. In the Shutdown state, the VM has everything ready 310 except that CPU execution is not scheduled by the hypervisor and VM's 311 memory is not resident in the hypervisor. The transition from the 312 Shutdown state to the Running state normally requires human action or 313 a system triggered event. Running state indicates the VM is in the 314 normal execution state. As part of transitioning the VM to the 315 Running state, the hypervisor must also provision network 316 connectivity for the VM's TSI(s) so that Ethernet frames can be sent 317 and received correctly. Initially, when Running, no ongoing 318 migration, suspension or shutdown is in process. 320 In the VM creation phase, the VM's TSI has to be associated with the 321 external NVE. Association here indicates that hypervisor and the 322 external NVE have signaled each other and reached some agreement. 323 Relevant networking parameters or information have been provisioned 324 properly. The External NVE should be informed of the VM's TSI MAC 325 address and/or IP address. In addition to external network 326 connectivity, the hypervisor may provide local network connectivity 327 between the VM's TSI and other VM's TSI that are co-resident on the 328 same hypervisor. When the intra- or inter-hypervisor connectivity is 329 extended to the external NVE, a locally significant tag, e.g. VLAN 330 ID, should be used between the hypervisor and the external NVE to 331 differentiate each VN's traffic. Both the hypervisor and external NVE 332 sides must agree on that tag value for traffic identification, 333 isolation, and forwarding. 335 The external NVE may need to do some preparation before it signals 336 successful association with the TSI. Such preparation may include 337 locally saving the states and binding information of the tenant 338 system interface and its VN, communicating with the NVA for network 339 provisioning, etc. 341 Tenant System interface association should be performed before the VM 342 enters the Running state, preferably in the Shutdown state. If 343 association with an external NVE fails, the VM should not go into the 344 Running state. 346 2.2 VM Live Migration Event 348 Live migration is sometimes referred to as "hot" migration in that, 349 from an external viewpoint, the VM appears to continue to run while 350 being migrated to another server (e.g., TCP connections generally 351 survive this class of migration). In contrast, "cold" migration 352 consists of shutting down VM execution on one server and restarting 353 it on another. For simplicity, the following abstract summary of live 354 migration assumes shared storage, so that the VM's storage is 355 accessible to the source and destination servers. Assume VM live 356 migrates from hypervisor 1 to hypervisor 2. Such a migration event 357 involves state transitions on both source hypervisor 1 and 358 destination hypervisor 2. The VM state on source hypervisor 1 359 transits from Running to Migrating and then to Shutdown [RFC7666]. 360 The VM state on destination hypervisor 2 transits from Shutdown to 361 Migrating and then Running. 363 The external NVE connected to destination hypervisor 2 has to 364 associate the migrating VM's TSI with it by discovering the TSI's MAC 365 and/or IP addresses, its VN, locally significant VLAN ID if any, and 366 provisioning other network related parameters of the TSI. The 367 external NVE may be informed about the VM's peer VMs, storage devices 368 and other network appliances with which the VM needs to communicate 369 or is communicating. The migrated VM on destination hypervisor 2 370 should not go to Running state until all the network provisioning and 371 binding has been done. 373 The migrating VM should not be in Running state at the same time on 374 the source hypervisor and destination hypervisor during migration. 375 The VM on the source hypervisor does not transition into Shutdown 376 state until the VM successfully enters the Running state on the 377 destination hypervisor. It is possible that the VM on the source 378 hypervisor stays in Migrating state for a while after the VM on the 379 destination hypervisor enters Running state. 381 2.3 VM Termination Event 383 A VM termination event is also referred to as "powering off" a VM. A 384 VM termination event leads to its state becoming Shutdown. There are 385 two possible causes of VM termination [RFC7666]. One is the normal 386 "power off" of a running VM; the other is that the VM has been 387 migrated to another hypervisor and the VM image on the source 388 hypervisor has to stop executing and be shutdown. 390 In VM termination, the external NVE connecting to that VM needs to 391 deprovision the VM, i.e. delete the network parameters associated 392 with that VM. In other words, the external NVE has to de-associate 393 the VM's TSI. 395 2.4 VM Pause, Suspension and Resumption Events 397 A VM pause event leads to the VM transiting from Running state to 398 Paused state. The Paused state indicates that the VM is resident in 399 memory but no longer scheduled to execute by the hypervisor 400 [RFC7666]. The VM can be easily re-activated from Paused state to 401 Running state. 403 A VM suspension event leads to the VM transiting from Running state 404 to Suspended state. A VM resumption event leads to the VM transiting 405 state from Suspended state to Running state. Suspended state means 406 the memory and CPU execution state of the virtual machine are saved 407 to persistent store. During this state, the virtual machine is not 408 scheduled to execute by the hypervisor [RFC7666]. 410 In the Split-NVE architecture, the external NVE SHOULD NOT 411 disassociate the paused or suspended VM as the VM can return to 412 Running state at any time. 414 3. Hypervisor-to-NVE Control Plane Protocol Functionality 415 The following subsections show illustrative examples of the state 416 transitions of an external NVE which are relevant to Hypervisor-to- 417 NVE Signaling protocol functionality. It should be noted this is not 418 prescriptive text for the full state machine. 420 3.1 VN Connect and Disconnect 422 In the Split-NVE scenario, a protocol is needed between the End 423 Device (e.g. Hypervisor) and the external NVE it is using in order to 424 make the external NVE aware of the changing VN membership 425 requirements of the Tenant Systems within the End Device. 427 A key driver for using a protocol rather than using static 428 configuration of the external NVE is because the VN connectivity 429 requirements can change frequently as VMs are brought up, moved, and 430 brought down on various hypervisors throughout the data center or 431 external cloud. 433 +---------------+ Receive VN_connect; +-------------------+ 434 |VN_Disconnected| return Local_Tag value |VN_Connected | 435 +---------------+ for VN if successful; +-------------------+ 436 |VN_ID; |-------------------------->|VN_ID; | 437 |VN_State= | |VN_State=connected;| 438 |disconnected; | |Num_TSI_Associated;| 439 | |<--Receive VN_disconnect---|Local_Tag; | 440 +---------------+ |VN_Context; | 441 +-------------------+ 443 Figure 5. State Transition Example of a VAP Instance 444 on an External NVE 446 Figure 5 shows the state transition for a VAP on the external NVE. An 447 NVE that supports the hypervisor to NVE control plane protocol should 448 support one instance of the state machine for each active VN. The 449 state transition on the external NVE is normally triggered by the 450 hypervisor-facing side events and behaviors. Some of the interleaved 451 interaction between NVE and NVA will be illustrated to better explain 452 the whole procedure; while others of them may not be shown. 454 The external NVE MUST be notified when an End Device requires 455 connection to a particular VN and when it no longer requires 456 connection. In addition, the external NVE must provide a local tag 457 value for each connected VN to the End Device to use for exchanging 458 packets between the End Device and the external NVE (e.g. a locally 459 significant [IEEE 802.1Q] tag value). How "local" the significance is 460 depends on whether the Hypervisor has a direct physical connection to 461 the external NVE (in which case the significance is local to the 462 physical link), or whether there is an Ethernet switch (e.g. a blade 463 switch) connecting the Hypervisor to the NVE (in which case the 464 significance is local to the intervening switch and all the links 465 connected to it). 467 These VLAN tags are used to differentiate between different VNs as 468 packets cross the shared access network to the external NVE. When the 469 external NVE receives packets, it uses the VLAN tag to identify their 470 VN coming from a given TSI, strips the tag, adds the appropriate 471 overlay encapsulation for that VN, and sends it towards the 472 corresponding remote NVE across the underlying IP network. 474 The Identification of the VN in this protocol could either be through 475 a VN Name or a VN ID. A globally unique VN Name facilitates 476 portability of a Tenant's Virtual Data Center. Once an external NVE 477 receives a VN connect indication, the NVE needs a way to get a VN 478 Context allocated (or receive the already allocated VN Context) for a 479 given VN Name or ID (as well as any other information needed to 480 transmit encapsulated packets). How this is done is the subject of 481 the NVE-to-NVA protocol which are part of work items 1 and 2 in 482 [RFC7364]. 484 The VN_connect message can be explicit or implicit. Explicit means 485 the hypervisor sends a request message explicitly for the connection 486 to a VN. Implicit means the external NVE receives other messages, 487 e.g. very first TSI associate message (see the next subsection) for a 488 given VN, that implicitly indicate its interest in connecting to a 489 VN. 491 A VN_disconnect message indicates that the NVE can release all the 492 resources for that disconnected VN and transit to VN_disconnected 493 state. The local tag assigned for that VN can possibly be reclaimed 494 for use by another VN. 496 3.2 TSI Associate and Activate 498 Typically, a TSI is assigned a single MAC address and all frames 499 transmitted and received on that TSI use that single MAC address. As 500 mentioned earlier, it is also possible for a Tenant System to 501 exchange frames using multiple MAC addresses or packets with multiple 502 IP addresses. 504 Particularly in the case of a TS that is forwarding frames or packets 505 from other TSs, the external NVE will need to communicate the mapping 506 between the NVE's IP address on the underlying network and ALL the 507 addresses the TS is forwarding on behalf of the corresponding VN to 508 the NVA. 510 The NVE has two ways it can discover the tenant addresses for which 511 frames are to be forwarded to a given End Device (and ultimately to 512 the TS within that End Device). 514 1. It can glean the addresses by inspecting the source addresses in 515 packets it receives from the End Device. 517 2. The hypervisor can explicitly signal the address associations of 518 a TSI to the external NVE. An address association includes all the 519 MAC and/or IP addresses possibly used as source addresses in a packet 520 sent from the hypervisor to external NVE. The external NVE may 521 further use this information to filter the future traffic from the 522 hypervisor. 524 To use the second approach above, the "hypervisor-to-NVE" protocol 525 must support End Devices communicating new tenant addresses 526 associations for a given TSI within a given VN. 528 Figure 6 shows the example of a state transition for a TSI connecting 529 to a VAP on the external NVE. An NVE that supports the hypervisor to 530 NVE control plane protocol may support one instance of the state 531 machine for each TSI connecting to a given VN. 533 disassociate +--------+ disassociate 534 +--------------->| Init |<--------------------+ 535 | +--------+ | 536 | | | | 537 | | | | 538 | +--------+ | 539 | | | | 540 | associate | | activate | 541 | +-----------+ +-----------+ | 542 | | | | 543 | | | | 544 | \|/ \|/ | 545 +--------------------+ +---------------------+ 546 | Associated | | Activated | 547 +--------------------+ +---------------------+ 548 |TSI_ID; | |TSI_ID; | 549 |Port; |-----activate---->|Port; | 550 |VN_ID; | |VN_ID; | 551 |State=associated; | |State=activated ; |-+ 552 +-|Num_Of_Addr; |<---deactivate ---|Num_Of_Addr; | | 553 | |List_Of_Addr; | |List_Of_Addr; | | 554 | +--------------------+ +---------------------+ | 555 | /|\ /|\ | 556 | | | | 557 +---------------------+ +-------------------+ 558 add/remove/updt addr; add/remove/updt addr; 559 or update port; or update port; 561 Figure 6 State Transition Example of a TSI Instance 562 on an External NVE 564 The Associated state of a TSI instance on an external NVE indicates 565 all the addresses for that TSI have already associated with the VAP 566 of the external NVE on a given port e.g. on port p for a given VN but 567 no real traffic to and from the TSI is expected and allowed to pass 568 through. An NVE has reserved all the necessary resources for that 569 TSI. An external NVE may report the mappings of its underlay IP 570 address and the associated TSI addresses to NVA and relevant network 571 nodes may save such information to their mapping tables but not their 572 forwarding tables. An NVE may create ACL or filter rules based on the 573 associated TSI addresses on that attached port p but not enable them 574 yet. The local tag for the VN corresponding to the TSI instance 575 should be provisioned on port p to receive packets. 577 The VM migration event (discussed section 2) may cause the hypervisor 578 to send an associate message to the NVE connected to the destination 579 hypervisor of the migration. A VM creation event may also cause to 580 the same practice. 582 The Activated state of a TSI instance on an external NVE indicates 583 that all the addresses for that TSI are functioning correctly on a 584 given port e.g. port p and traffic can be received from and sent to 585 that TSI via the NVE. The mappings of the NVE's underlay IP address 586 and the associated TSI addresses should be put into the forwarding 587 table rather than the mapping table on relevant network nodes. ACL or 588 filter rules based on the associated TSI addresses on the attached 589 port p in the NVE are enabled. The local tag for the VN corresponding 590 to the TSI instance MUST be provisioned on port p to receive packets. 592 The Activate message makes the state transit from Init or Associated 593 to Activated. VM creation, VM migration, and VM resumption events 594 discussed in Section 4 may trigger sending the Activate message from 595 the hypervisor to the external NVE. 597 TSI information may get updated in either the Associated or Activated 598 state. The following are considered updates to the TSI information: 599 add or remove the associated addresses, update the current associated 600 addresses (for example updating IP for a given MAC), and update the 601 NVE port information based on where the NVE receives messages. Such 602 updates do not change the state of TSI. When any address associated 603 with a given TSI changes, the NVE should inform the NVA to update the 604 mapping information for NVE's underlying address and the associated 605 TSI addresses. The NVE should also change its local ACL or filter 606 settings accordingly for the relevant addresses. Port information 607 updates will cause the provisioning of the local tag for the VN 608 corresponding to the TSI instance on new port and removal from the 609 old port. 611 3.3 TSI Disassociate and Deactivate 613 Disassociate and deactivate behaviors are conceptually the reverse of 614 associate and activate. 616 From Activated state to Associated state, the external NVE needs to 617 make sure the resources are still reserved but the addresses 618 associated to the TSI are not functioning. No traffic to or from the 619 TSI is expected or allowed to pass through. For example, the NVE 620 needs to tell the NVA to remove the relevant addresses mapping 621 information from forwarding and routing tables. ACL and filtering 622 rules regarding the relevant addresses should be disabled. 624 From Associated or Activated state to the Init state, the NVE 625 releases all the resources relevant to TSI instances. The NVE should 626 also inform the NVA to remove the relevant entries from mapping 627 table. ACL or filtering rules regarding the relevant addresses should 628 be removed. Local tag provisioning on the connecting port on NVE 629 SHOULD be cleared. 631 A VM suspension event (discussed in section 2) may cause the relevant 632 TSI instance(s) on the NVE to transit from Activated to Associated 633 state. 635 A VM pause event normally does not affect the state of the relevant 636 TSI instance(s) on the NVE as the VM is expected to run again soon. 638 A VM shutdown event will normally cause the relevant TSI instance(s) 639 on the NVE to transition to Init state from Activated state. All 640 resources should be released. 642 A VM migration will cause the TSI instance on the source NVE to leave 643 Activated state. When a VM migrates to another hypervisor connecting 644 to the same NVE, i.e. source and destination NVE are the same, NVE 645 should use TSI_ID and incoming port to differentiate two TSI 646 instances. 648 Although the triggering messages for the state transition shown in 649 Figure 6 does not indicate the difference between a VM 650 creation/shutdown event and a VM migration arrival/departure event, 651 the external NVE can make optimizations if it is given such 652 information. For example, if the NVE knows the incoming activate 653 message is caused by migration rather than VM creation, some 654 mechanisms may be employed or triggered to make sure the dynamic 655 configurations or provisionings on the destination NVE are the same 656 as those on the source NVE for the migrated VM. For example an IGMP 657 query [RFC2236] can be triggered by the destination external NVE to 658 the migrated VM so that VM is forced to send an IGMP report to the 659 multicast router. Then a multicast router can correctly route the 660 multicast traffic to the new external NVE for those multicast groups 661 the VM joined before the migration. 663 4. Hypervisor-to-NVE Control Plane Protocol Requirements 665 Req-1: The protocol MUST support a bridged network connecting End 666 Devices to the External NVE. 668 Req-2: The protocol MUST support multiple End Devices sharing the 669 same External NVE via the same physical port across a bridged 670 network. 672 Req-3: The protocol MAY support an End Device using multiple external 673 NVEs simultaneously, but only one external NVE for each VN. 675 Req-4: The protocol MAY support an End Device using multiple external 676 NVEs simultaneously for the same VN. 678 Req-5: The protocol MUST allow the End Device to initiate a request 679 to its associated External NVE to be connected/disconnected to a 680 given VN. 682 Req-6: The protocol MUST allow an External NVE initiating a request 683 to its connected End Devices to be disconnected from a given VN. 685 Req-7: When a TS attaches to a VN, the protocol MUST allow for an End 686 Device and its external NVE to negotiate one or more locally- 687 significant tag(s) for carrying traffic associated with a specific VN 688 (e.g., [IEEE 802.1Q] tags). 690 Req-8: The protocol MUST allow an End Device initiating a request to 691 associate/disassociate and/or activate/deactive some or all 692 address(es) of a TSI instance to a VN on an NVE port. 694 Req-9: The protocol MUST allow the External NVE initiating a request 695 to disassociate and/or deactivate some or all address(es) of a TSI 696 instance to a VN on an NVE port. 698 Req-10: The protocol MUST allow an End Device initiating a request to 699 add, remove or update address(es) associated with a TSI instance on 700 the external NVE. Addresses can be expressed in different formats, 701 for example, MAC, IP or pair of IP and MAC. 703 Req-11: The protocol MUST allow the External NVE to authenticate the 704 End Device connected. 706 Req-12: The protocol MUST be able to run over L2 links between the 707 End Device and its External NVE. 709 Req-13: The protocol SHOULD support the End Device indicating if an 710 associate or activate request from it is the result of a VM hot 711 migration event. 713 5. VDP Applicability and Enhancement Needs 715 Virtual Station Interface (VSI) Discovery and Configuration Protocol 716 (VDP) [IEEE 802.1Q] can be the control plane protocol running between 717 the hypervisor and the external NVE. Appendix A illustrates VDP for 718 the reader's information. 720 VDP facilitates the automatic discovery and configuration of Edge 721 Virtual Bridging (EVB) stations and Edge Virtual Bridging (EVB) 722 bridges. An EVB station is normally an end station running multiple 723 VMs. It is conceptually equivalent to a hypervisor in this document. 724 An EVB bridge is conceptually equivalent to the external NVE. 726 VDP is able to pre-associate/associate/de-associate a VSI on an EVB 727 station with a port on the EVB bridge. A VSI is approximately the 728 concept of a virtual port by which a VM connects to the hypervisor in 729 this document's context. The EVB station and the EVB bridge can reach 730 agreement on VLAN ID(s) assigned to a VSI via VDP message exchange. 731 Other configuration parameters can be exchanged via VDP as well. VDP 732 is carried over the Edge Control Protocol(ECP) [IEEE 802.1Q] which 733 provides a reliable transportation over a layer 2 network. 735 VDP protocol needs some extensions to fulfill the requirements listed 736 in this document. Table 1 shows the needed extensions and/or 737 clarifications in the NVO3 context. 739 +------+-----------+-----------------------------------------------+ 740 | Req | Supported | remarks | 741 | | by VDP? | | 742 +------+-----------+-----------------------------------------------+ 743 | Req-1| | | 744 +------+ |Needs extension. Must be able to send to a | 745 | Req-2| |specific unicast MAC and should be able to send| 746 +------+ Partially |to a non-reserved well known multicast address | 747 | Req-3| |other than the nearest customer bridge address.| 748 +------+ | | 749 | Req-4| | | 750 +------+-----------+-----------------------------------------------+ 751 | Req-5| Yes |VN is indicated by GroupID | 752 +------+-----------+-----------------------------------------------+ 753 | Req-6| Yes |Bridge sends De-Associate | 754 +------+-----------+------------------------+----------------------+ 755 | | |VID==NULL in request and bridge returns the | 756 | Req-7| Yes |assigned value in response or specify GroupID | 757 | | |in request and get VID assigned in returning | 758 | | |response. Multiple VLANs per group are allowed.| 759 +------+-----------+------------------------+----------------------+ 760 | | | requirements | VDP equivalence | 761 | | +------------------------+----------------------+ 762 | | | associate/disassociate|pre-asso/de-associate | 763 | Req-8| Partially | activate/deactivate |associate/de-associate| 764 | | +------------------------+----------------------| 765 | | |Needs extension to allow associate->pre-assoc | 766 +------+-----------+------------------------+----------------------+ 767 | Req-9| Yes | VDP bridge initiates de-associate | 768 +------+-----------+-----------------------------------------------+ 769 |Req-10| Partially |Needs extension for IPv4/IPv6 address. Add a | 770 | | |new "filter info format" type. | 771 +------+-----------+-----------------------------------------------+ 772 |Req-11| No |Out-of-band mechanism is preferred, e.g. MACSec| 773 | | |or 802.1X. | 774 +------+-----------+-----------------------------------------------+ 775 |Req-12| Yes |L2 protocol naturally | 776 +------+-----------+-----------------------------------------------+ 777 | | |M bit for migrated VM on destination hypervisor| 778 | | |and S bit for that on source hypervisor. | 779 |Req-13| Partially |It is indistinguishable when M/S is 0 between | 780 | | |no guidance and events not caused by migration | 781 | | |where NVE may act differently. Needs new | 782 | | |New bits for migration indication in new | 783 | | |"filter info format" type. | 784 +------+-----------+-----------------------------------------------+ 785 Table 1 Compare VDP with the requirements 787 Simply adding the ability to carry layer 3 addresses, VDP can serve 788 the Hypervisor-to-NVE control plane functions pretty well. Other 789 extensions are the improvement of the protocol capabilities for 790 better fit in an NVO3 network. 792 6. Security Considerations 794 NVEs must ensure that only properly authorized Tenant Systems are 795 allowed to join and become a part of any particular Virtual Network. 796 In addition, NVEs will need appropriate mechanisms to ensure that any 797 hypervisor wishing to use the services of an NVE are properly 798 authorized to do so. One design point is whether the hypervisor 799 should supply the NVE with necessary information (e.g., VM addresses, 800 VN information, or other parameters) that the NVE uses directly, or 801 whether the hypervisor should only supply a VN ID and an identifier 802 for the associated VM (e.g., its MAC address), with the NVE using 803 that information to obtain the information needed to validate the 804 hypervisor-provided parameters or obtain related parameters in a 805 secure manner. 807 7. IANA Considerations 809 No IANA action is required. RFC Editor: please delete this section 810 before publication. 812 8. Acknowledgements 813 This document was initiated based on the merger from the drafts 814 draft-kreeger-nvo3-hypervisor-nve-cp, draft-gu-nvo3-tes-nve- 815 mechanism, and draft-kompella-nvo3-server2nve. Thanks to all the co- 816 authors and contributing members of those drafts. 818 The authors would like to specially thank Lucy Yong and Jon Hudson 819 for their generous help in improving this document. 821 8. References 823 8.1 Normative References 825 [RFC7365] Lasserre, M., Balus, F., Morin, T., Bitar, N., and Y. 826 Rekhter, "Framework for DC Network Virtualization", 827 October 2014. 829 [RFC7666] Asai H., MacFaden M., Schoenwaelder J., Shima K., Tsou T., 830 "Management Information Base for Virtual Machines 831 Controlled by a Hypervisor", October 2015. 833 [RFC8014] Black, D., Hudson, J., Kreeger, L., Lasserre, M., Narten, 834 T., "An Architecture for Data-Center Network 835 Virtualization over Layer 3 (NVO3)", December 2016. 837 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 838 Key Words ", BCP 14, RFC 8174, May 2017. 840 [IEEE 802.1Q] IEEE, "Media Access Control (MAC) Bridges and Virtual 841 Bridged Local Area Networks", IEEE Std 802.1Q-2014, 842 November 2014. 844 8.2 Informative References 846 [RFC2236] Fenner, W., "Internet Group Management Protocol, Version 847 2", RFC 2236, November 1997. 849 [RFC4122] Leach, P., Mealling, M., and R. Salz, "A Universally 850 Unique IDentifier (UUID) URN Namespace", RFC 4122, July 851 2005. 853 [RFC7364] Narten, T., Gray, E., Black, D., Fang, L., Kreeger, L., and 854 M. Napierala, "Problem Statement: Overlays for Network 855 Virtualization", October 2014. 857 Appendix A. IEEE 802.1Q VDP Illustration (For information only) 859 The VDP (VSI Discovery and Discovery and Configuration Protocol [IEEE 860 802.1Q]) can be considered as a controlling protocol running between 861 the hypervisor and the external bridge. VDP association TLV structure 862 are formatted as shown in Figure A.1. 864 +--------+--------+------+-----+--------+------+------+------+------+ 865 |TLV type|TLV info|Status|VSI |VSI Type|VSI ID|VSI ID|Filter|Filter| 866 | |string | |Type |Version |Format| |Info |Info | 867 | |length | |ID | | | |format| | 868 +--------+--------+------+-----+--------+------+------+------+------+ 869 | | |<----VSI type&instance----->|<--Filter--->| 870 | | |<-------------VSI attributes------------->| 871 |<--TLV header--->|<-----------TLV information string ------------->| 873 Figure A.1: VDP association TLV 875 There are basically four TLV types. 877 1. Pre-associate: Pre-associate is used to pre-associate a VSI 878 instance with a bridge port. The bridge validates the request and 879 returns a failure Status in case of errors. Successful pre-associate 880 does not imply that the indicated VSI Type or provisioning will be 881 applied to any traffic flowing through the VSI. The pre-associate 882 enables faster response to an associate, by allowing the bridge to 883 obtain the VSI Type prior to an association. 885 2. Pre-associate with resource reservation: Pre-associate with 886 Resource Reservation involves the same steps as Pre-associate, but on 887 success it also reserves resources in the bridge to prepare for a 888 subsequent Associate request. 890 3. Associate: Associate creates and activates an association between 891 a VSI instance and a bridge port. An bridge allocates any required 892 bridge resources for the referenced VSI. The bridge activates the 893 configuration for the VSI Type ID. This association is then applied 894 to the traffic flow to/from the VSI instance. 896 4. De-associate: The de-associate is used to remove an association 897 between a VSI instance and a bridge port. Pre-associated and 898 associated VSIs can be de-associated. De-associate releases any 899 resources that were reserved as a result of prior associate or pre- 900 Associate operations for that VSI instance. 902 De-associate can be initiated by either side and the other types can 903 only be initiated by the server side. 905 Some important flag values in VDP Status field: 907 1. M-bit (Bit 5): Indicates that the user of the VSI (e.g., the VM) 908 is migrating (M-bit = 1) or provides no guidance on the migration of 909 the user of the VSI (M-bit = 0). The M-bit is used as an indicator 910 relative to the VSI that the user is migrating to. 912 2. S-bit (Bit 6): Indicates that the VSI user (e.g., the VM) is 913 suspended (S-bit = 1) or provides no guidance as to whether the user 914 of the VSI is suspended (S-bit = 0). A keep-alive Associate request 915 with S-bit = 1 can be sent when the VSI user is suspended. The S-bit 916 is used as an indicator relative to the VSI that the user is 917 migrating from. 919 The filter information format currently defines 4 types. Each of the 920 filter information is shown in details as follows. 922 1. VID Filter Info format 923 +---------+------+-------+--------+ 924 | #of | PS | PCP | VID | 925 |entries |(1bit)|(3bits)|(12bits)| 926 |(2octets)| | | | 927 +---------+------+-------+--------+ 928 |<--Repeated per entry->| 930 Figure A.2 VID Filter Info format 932 2. MAC/VID Filter Info format 933 +---------+--------------+------+-------+--------+ 934 | #of | MAC address | PS | PCP | VID | 935 |entries | (6 octets) |(1bit)|(3bits)|(12bits)| 936 |(2octets)| | | | | 937 +---------+--------------+------+-------+--------+ 938 |<--------Repeated per entry---------->| 940 Figure A.3 MAC/VID filter format 942 3. GroupID/VID Filter Info format 943 +---------+--------------+------+-------+--------+ 944 | #of | GroupID | PS | PCP | VID | 945 |entries | (4 octets) |(1bit)|(3bits)|(12bits)| 946 |(2octets)| | | | | 947 +---------+--------------+------+-------+--------+ 948 |<--------Repeated per entry---------->| 950 Figure A.4 GroupID/VID filter format 952 4. GroupID/MAC/VID Filter Info format 953 +---------+----------+-------------+------+-----+--------+ 954 | #of | GroupID | MAC address | PS | PCP | VID | 955 |entries |(4 octets)| (6 octets) |(1bit)|(3b )|(12bits)| 956 |(2octets)| | | | | | 957 +---------+----------+-------------+------+-----+--------+ 958 |<-------------Repeated per entry------------->| 959 Figure A.5 GroupID/MAC/VID filter format 961 The null VID can be used in the VDP Request sent from the station to 962 the external bridge. Use of the null VID indicates that the set of 963 VID values associated with the VSI is expected to be supplied by the 964 bridge. The set of VID values is returned to the station via the VDP 965 Response. The returned VID value can be a locally significant value. 966 When GroupID is used, it is equivalent to the VN ID in NVO3. GroupID 967 will be provided by the station to the bridge. The bridge maps 968 GroupID to a locally significant VLAN ID. 970 The VSI ID in VDP association TLV that identify a VM can be one of 971 the following format: IPV4 address, IPV6 address, MAC address, UUID 972 [RFC4122], or locally defined. 974 Authors' Addresses 976 Yizhou Li 977 Huawei Technologies 978 101 Software Avenue, 979 Nanjing 210012 980 China 982 Phone: +86-25-56625409 983 EMail: liyizhou@huawei.com 985 Donald Eastlake 986 Huawei R&D USA 987 155 Beaver Street 988 Milford, MA 01757 USA 990 Phone: +1-508-333-2270 991 EMail: d3e3e3@gmail.com 993 Lawrence Kreeger 994 Arrcus, Inc 995 Email: lkreeger@gmail.com 997 Thomas Narten 998 IBM 1000 Email: narten@us.ibm.com 1002 David Black 1003 Dell EMC 1004 176 South Street, 1005 Hopkinton, MA 01748 USA 1007 Email: david.black@dell.com