H3C SR6600 Routers. High Availability. Configuration Guide. Hangzhou H3C Technologies Co., Ltd.

Transcription

1 H3C SR6600 Routers High Availability Configuration Guide Hangzhou H3C Technologies Co., Ltd. Document Version: C-1.08 Product Version: SR6600-CMW520-R2420

2 Copyright , Hangzhou H3C Technologies Co., Ltd. and its licensors All Rights Reserved No part of this manual may be reproduced or transmitted in any form or by any means without prior written consent of Hangzhou H3C Technologies Co., Ltd. Trademarks H3C,, Aolynk,, H 3 Care,, TOP G,, IRF, NetPilot, Neocean, NeoVTL, SecPro, SecPoint, SecEngine, SecPath, Comware, Secware, Storware, NQA, VVG, V 2 G, V n G, PSPT, XGbus, N-Bus, TiGem, InnoVision and HUASAN are trademarks of Hangzhou H3C Technologies Co., Ltd. All other trademarks that may be mentioned in this manual are the property of their respective owners. Notice The information in this document is subject to change without notice. Every effort has been made in the preparation of this document to ensure accuracy of the contents, but all statements, information, and recommendations in this document do not constitute the warranty of any kind, express or implied.

3 Preface The H3C SR6600 documentation set includes 13 configuration guides, which describe the software features for the H3C SR6600 Routers and guide you through the software configuration procedures. These configuration guides also provide configuration examples to help you apply software features to different network scenarios. The High Availability Configuration Guide describes the fundamentals and configuration of high availabilities mechanisms and features supported on the H3C SR6600 routers, including active and standby switchover, stateful failover, CFD, DLDP, Ethernet OAM, RPR, RRPP, VRRP, and BFD. This preface includes: Audience Conventions About the H3C SR6600 Documentation Set Obtaining Documentation Technical Support Documentation Feedback Audience This documentation is intended for: Network planners Field technical support and servicing engineers Network administrators working with the SR6600 Conventions This section describes the conventions used in this documentation set. Command conventions Convention Boldface italic [ ] { x y... } [ x y... ] { x y... } * Description Bold text represents commands and keywords that you enter literally as shown. Italic text represents arguments that you replace with actual values. Square brackets enclose syntax choices (keywords or arguments) that are optional. Braces enclose a set of required syntax choices separated by vertical bars, from which you select one. Square brackets enclose a set of optional syntax choices separated by vertical bars, from which you select one or none. Asterisk marked braces enclose a set of required syntax choices separated by vertical bars, from which you select at least one. [ x y... ] * Asterisk marked square brackets enclose optional syntax choices separated by

4 Convention Description vertical bars, from which you may select multiple choices or none. &<1-n> The argument or keyword and argument combination before the ampersand (&) sign can be entered 1 to n times. # A line that starts with a pound (#) sign is comments. GUI conventions Boldface > Convention Description Window names, button names, field names, and menu items are in Boldface. For example, the New User window appears; click OK. Multi-level menus are separated by angle brackets. For example, File > Create > Folder. Symbols Convention Description Means reader be extremely careful. Improper operation may cause bodily injury. Means reader be careful. Improper operation may cause data loss or damage to equipment. Means an action or information that needs special attention to ensure successful configuration or good performance. Means a complementary description. Means techniques helpful for you to make configuration with ease. Network topology icons Convention Description Represents a generic network device, such as a router, switch, or firewall. Represents a routing-capable device, such as a router or Layer 3 switch. Represents a generic switch, such as a Layer 2 or Layer 3 switch, or a router that supports Layer 2 forwarding and other Layer 2 features. About the H3C SR6600 Documentation Set The H3C SR6600 documentation set includes: Category Documents Purposes Product description and specifications Marketing brochures Technology white papers Card datasheets Describe product specifications and benefits. Provide an in-depth description of software features and technologies. Describe card specifications, features, and standards.

5 Category Documents Purposes Hardware specifications and installation Software configuration Operations and maintenance Compliance and safety manual Installation guide Card manuals H3C N68 Cabinet Installation and Remodel Introduction Configuration guides Command references H3C SR6608 Release notes H3C SR6602 Release notes Provides regulatory information and the safety instructions that must be followed during installation. Provides a complete guide to hardware installation and hardware specifications. Provide the hardware specifications of cards. Guides you through installing and remodeling H3C N68 cabinets. Describe software features and configuration procedures. Provide a quick reference to all available commands. Provide information about the product release, including the version history, hardware and software compatibility matrix, version upgrade information, technical support information, and software upgrading. Obtaining Documentation You can access the most up-to-date H3C product documentation on the World Wide Web at Click the links on the top navigation bar to obtain different categories of product documentation: [Technical Support & Documents > Technical Documents] Provides hardware installation, software upgrading, and software feature configuration and maintenance documentation. [Products & Solutions] Provides information about products and technologies, as well as solutions. [Technical Support & Documents > Software Download] Provides the documentation released with the software version. Technical Support customer_service@h3c.com Documentation Feedback You can your comments about product documentation to info@h3c.com. We appreciate your comments.

6 Table of Contents 1 High Availability Overview 1-1 Availability Requirements 1-1 Availability Evaluation 1-1 High Availability Technologies 1-2 Fault Detection Technologies 1-2 Protection Switchover Technologies Active and Standby Switchover Configuration 2-1 Introduction to Active and Standby Switchover 2-1 Active and Standby Switchover Configuration Task List 2-2 Ignoring Version Check of the SMB 2-2 Restarting the SMB 2-2 Manually Performing an Active and Standby Switchover 2-3 Displaying and Maintaining Active and Standby Switchover Ethernet OAM Configuration 3-1 Ethernet OAM Overview 3-1 Background 3-1 Major Functions of Ethernet OAM 3-1 Ethernet OAMPDUs 3-2 How Ethernet OAM Works 3-3 Standards and Protocols 3-5 Ethernet OAM Configuration Task List 3-5 Configuring Basic Ethernet OAM Functions 3-6 Configuring the Ethernet OAM Connection Detection Timers 3-6 Configuring Link Monitoring 3-7 Configuring Errored Symbol Event Detection 3-7 Configuring Errored Frame Event Detection 3-7 Configuring Errored Frame Period Event Detection 3-8 Configuring Errored Frame Seconds Event Detection 3-8 Enabling OAM Remote Loopback 3-8 Displaying and Maintaining Ethernet OAM Configuration 3-9 Ethernet OAM Configuration Example CFD Configuration 4-1 Overview 4-1 Basic Concepts in CFD 4-1 CFD Functions 4-4 Protocols and Standards 4-5 CFD Configuration Task List 4-5 Configuring Basic CFD Settings 4-6 Enabling CFD 4-6 Configuring the CFD Protocol Version 4-6 i

7 Configuring Service Instances 4-6 Configuring MEPs 4-7 Configuring MIP Generation Rules 4-7 Configuring CFD Functions 4-9 Configuration Prerequisites 4-9 Configuring CC on MEPs 4-9 Configuring LB on MEPs 4-9 Configuring LT on MEPs 4-10 Displaying and Maintaining CFD 4-10 CFD Configuration Example DLDP Configuration 5-1 Overview 5-1 Background 5-1 How DLDP Works 5-2 DLDP Configuration Task List 5-8 Configuring the Duplex Mode and Speed of a Port 5-8 Enabling DLDP 5-9 Setting DLDP Mode 5-10 Setting the Interval for Sending Advertisement Packets 5-10 Setting the DelayDown Timer 5-10 Setting the Port Shutdown Mode 5-11 Configuring DLDP Authentication 5-12 Resetting DLDP State 5-12 Displaying and Maintaining DLDP 5-13 DLDP Configuration Example 5-13 Troubleshooting RPR Configuration 6-1 Introduction to RPR 6-1 Overview 6-1 Ring Structure of RPR 6-2 Data Operations on RPR 6-2 Topology Discovery 6-4 Fault Response Method 6-4 Centralized RPR and Distributed RPR 6-6 RPR Interface 6-6 Protocols and Standards 6-7 RPR Configuration Task List 6-7 Configuring Basic RPR Functions 6-8 Creating and Configuring an RPR Logical Interface 6-8 Binding an RPR Logical Interface with Physical Ports 6-9 Enabling RPR Mate Port Smart Connection 6-9 Configuring an RPR POS Interface 6-10 Configuring the RPR Station Name 6-10 Configuring RPR Protection 6-11 Configuring the RPR Protection Mode 6-11 ii

8 Configuring RPR Protection Reversion Mode 6-11 Manually Sending a Protection Request 6-11 Configuring the Ringlet Selection Table 6-12 Adding a Static Ringlet Selection Entry 6-12 Configuring Default Ringlet Selection 6-13 Configuring the RPR Fairness Algorithm 6-13 Configuring Reserved Bandwidth or Rate Limiting 6-13 Configuring Station Weight 6-14 Configuring RPR Timers 6-14 Configuring the ATD Timer 6-15 Configuring the Hold Off Timer 6-15 Configuring the Keepalive Timer 6-15 Configuring the Topology Stability Timer 6-16 Configuring the TC Timers 6-16 Configuring the TP Timers 6-16 Configuring the WTR Timer 6-17 Testing Connectivity Between RPR Stations 6-17 Displaying and Maintaining RPR 6-18 RPR Configuration Examples 6-18 RPR Interface Binding Configuration Example 6-18 RPR Protection Mode/Static Ringlet Selection Configuration Example RRPP Configuration 7-1 RRPP Overview 7-1 Background 7-1 Basic Concepts in RRPP 7-2 RRPPDUs 7-4 RRPP Timers 7-5 How RRPP Works 7-5 Typical RRPP Networking 7-6 Protocols and Standards 7-9 RRPP Configuration Task List 7-10 Creating an RRPP Domain 7-10 Configuring Control VLANs 7-11 Configuring Protected VLANs 7-11 Configuring RRPP Rings 7-12 Configuring RRPP Ports 7-12 Configuring RRPP Nodes 7-13 Activating an RRPP Domain 7-15 Configuring RRPP Timers 7-15 Configuring an RRPP Ring Group 7-16 Displaying and Maintaining RRPP 7-17 RRPP Configuration Examples 7-17 Single Ring Configuration Example 7-17 Intersecting Ring Configuration Example 7-19 Intersecting-Ring Load Balancing Configuration Example 7-24 iii

9 Troubleshooting Smart Link Configuration 8-1 Smart Link Overview 8-1 Background 8-1 Terminology 8-3 How Smart Link Works 8-3 Smart Link Configuration Task List 8-5 Configuring a Smart Link Router 8-5 Configuration Prerequisites 8-5 Configuring Protected VLANs for a Smart Link Group 8-6 Configuring Member Ports for a Smart Link Group 8-6 Configuring Role Preemption for a Smart Link Group 8-7 Enabling the Sending of Flush Messages 8-7 Configuring the Collaboration Between Smart Link and CC of CFD 8-8 Smart Link Router Configuration Example 8-8 Configuring an Associated Router 8-9 Enabling the Receiving of Flush Messages 8-9 Associated Router Configuration Example 8-10 Displaying and Maintaining Smart Link 8-10 Smart Link Configuration Examples 8-10 Single Smart Link Group Configuration Example 8-10 Multiple Smart Link Groups Load Sharing Configuration Example VRRP Configuration 9-1 VRRP Overview 9-1 VRRP Standard Protocol Mode 9-2 Introduction to VRRP Group 9-2 VRRP Timers 9-4 Packet Format 9-4 Principles of VRRP 9-6 VRRP Tracking 9-6 VRRP Application (Taking IPv4-Based VRRP for Example) 9-7 VRRP Load Balancing Mode 9-8 Overview 9-8 Assigning Virtual MAC Addresses 9-9 Virtual Forwarder 9-10 Packet Types 9-11 Configuring VRRP for IPv VRRP for IPv4 Configuration Task List 9-11 Mapping a Virtual IP Address to a MAC Address 9-12 Configuring VRRP Working Mode 9-13 Specifying the VRRP Control VLAN 9-14 Creating a VRRP Group and Configuring Virtual IP Address 9-15 Configuring Router Priority, Preemptive Mode and Tracking Function 9-17 Configuring VF Tracking 9-18 Configuring VRRP Packet Attributes 9-19 iv

10 Enabling the Trap Function for VRRP 9-20 Displaying and Maintaining VRRP for IPv Configuring VRRP for IPv VRRP for IPv6 Configuration Task List 9-21 Mapping a Virtual IPv6 Address to a MAC Address 9-21 Creating a VRRP Group and Configuring Virtual IPv6 Address 9-22 Configuring Router Priority, Preemptive Mode and Tracking Function 9-23 Configuring VF Tracking 9-24 Configuring VRRP Packet Attributes 9-25 Displaying and Maintaining VRRP for IPv IPv4-Based VRRP Configuration Examples 9-26 Single VRRP Group Configuration Example 9-26 VRRP Interface Tracking Configuration Example 9-28 Multiple VRRP Groups Configuration Example 9-31 VRRP Load Balancing Mode Configuration Example 9-33 IPv6-Based VRRP Configuration Examples 9-37 Single VRRP Group Configuration Example 9-37 VRRP Interface Tracking Configuration Example 9-40 Multiple VRRP Group Configuration Example 9-43 VRRP Load Balancing Mode Configuration Example 9-45 Troubleshooting VRRP Stateful Failover Configuration 10-1 Overview 10-1 Introduction to Stateful Failover 10-1 Introduction to Stateful Failover States 10-2 Introduction to Stateful Failover Configuration 10-2 Enabling Stateful Failover 10-3 Configuring the Failover Interface 10-3 Displaying and Maintaining Stateful Failover 10-4 Stateful Failover Configuration Example BFD Configuration 11-1 Introduction to BFD 11-1 How BFD Works 11-1 BFD Packet Format 11-4 Supported Features 11-5 Protocols and Standards 11-6 Configuring BFD Basic Functions 11-6 Configuration Prerequisites 11-6 Configuration Procedure 11-6 Enabling Trap 11-7 Displaying and Maintaining BFD Track Configuration 12-1 Track Overview 12-1 Collaboration Between the Track Module and a Detection Module 12-1 Collaboration Between the Track Module and an Application Module 12-2 v

11 Track Configuration Task List 12-2 Associating the Track Module with a Detection Module 12-3 Associating Track with NQA 12-3 Associating Track with BFD 12-3 Associating Track with Interface Management 12-4 Associating the Track Module with an Application Module 12-4 Associating Track with VRRP 12-4 Associating Track with Static Routing 12-6 Associating Track with Policy Routing 12-7 Displaying and Maintaining Track Entries 12-8 Track Configuration Examples 12-8 VRRP-Track-NQA Collaboration Configuration Example 12-8 Configuring BFD for a VRRP Backup to Monitor the Master Configuring BFD for the VRRP Master to Monitor the Uplink Static Routing-Track-NQA Collaboration Configuration Example Static Routing-Track-BFD Collaboration Configuration Example VRRP-Track-Interface Management Collaboration Configuration Example (The Master Monitors the Uplink Interface) Index 13-1 vi

12 1 High Availability Overview With the wide deployment of various types of value-added services such as IPTV and video conference, communication interruption may affect these services and result in serious lost. Therefore, as the carrier of services, the availability of basic network infrastructures is becoming a great concern. In an actual network, increasing fault tolerance capabilities of a system, increasing fault recovery speed, and reducing impact of faults on services are effective ways to enhance system availability. Availability Requirements Availability requirements fall into three levels based on purpose and implementation, as shown in Table 1-1. Table 1-1 Availability requirements Level Purpose Implementation Decrease system software and hardware faults Protect system functions from being affected if faults occur Enable the system to recover fast even if system functions are affected. Hardware: Simplifying circuit design, enhancing production techniques, and performing reliability tests. Software: Reliability design and test Device and link redundancy and deployment of switchover strategies Providing fault detection, diagnosis, isolation, and recovery technologies Among the availability requirements, the availability requirement of level 1 should be considered during the design and production process of network devices; the availability requirement of level 2 should be considered at the design of network infrastructure; the availability requirement of level 3 should be met by adopting corresponding high availability technologies during the deployment of a network according to the network infrastructure and service characteristics. This manual describes these high availability technologies. Availability Evaluation Typically, Mean Time Between Failures (MTBF) and Mean Time to Repair (MTTR) are used to evaluate the availability of a network. MTBF MTBF is the predicted elapsed time between inherent failures of a system during operation. It is typically in the unit of hours. A higher MTBF means a high availability. MTTR MTTR is the average time required to repair a failed system. MTTR in a broad sense also involves spare parts management and customer services. MTTR = fault detection time + hardware replacement time + system initialization time + link recovery time + routing time + forwarding recovery time. A smaller value of each item, a smaller MTTR and a higher availability. 1-1

13 High Availability Technologies As previously mentioned, increasing MTBF or decreasing MTTR can enhance the availability of a network. The high availability technologies described in this section meet the level 3 high availability requirements in the aspect of decreasing MTTR. High availability technologies can be classified into fault detection technologies and protection switchover technologies. Support for high availability technologies depends on your device model. Fault Detection Technologies Fault detection technologies enable detection and diagnosis of network faults. CFD, DLDP, Ethernet OAM, and MPLS OAM are data link layer fault detection technologies; BFD is a generic fault detection technology that can be used at any layer; NQA is used for diagnosis and evaluation of network quality; Monitor Link and Track work along with other high availability technologies to detect faults through a collaboration mechanism. See Table 1-2 for the details of these technologies. Table 1-2 Fault detection technologies Technology Introduction Reference CFD DLDP Ethernet OAM BFD NQA Connectivity Fault Detection (CFD), which conforms to IEEE 802.1ag Connectivity Fault Management (CFM) and ITU-T Y.1731, is an end-to-end per-vlan link layer Operations, Administration and Maintenance (OAM) mechanism used for link connectivity detection, fault verification, and fault location. The Device link detection protocol (DLDP) deals with unidirectional links that may occur in a network. On detecting a unidirectional link, DLDP, as configured, can shut down the related port automatically or prompt users to take actions to avoid network problems. As a tool monitoring Layer 2 link status, Ethernet OAM is mainly used to address common link-related issues on the last mile. You can monitor the status of the point-to-point link between two directly connected devices by enabling Ethernet OAM on them. Bidirectional forwarding detection (BFD) provides a single mechanism to quickly detect and monitor the connectivity of links or IP forwarding in networks. To improve network performance, devices must quickly detect communication failures to restore communication through backup paths as soon as possible. Network Quality Analyzer (NQA) analyzes network performance, services and service quality through sending test packets, and provides you with network performance and service quality parameters such as jitter, TCP connection delay, FTP connection delay and file transfer rate. CFD in the High Availability Configuration Guide DLDP in the High Availability Configuration Guide Ethernet OAM in the High Availability Configuration Guide BFD in the High Availability Configuration Guide NQA in the Network Management and Monitoring Configuration Guide 1-2

14 Technology Introduction Reference Track The track module is used to implement collaboration between different modules. The collaboration here involves three parts: the application modules, the track module, and the detection modules. These modules collaborate with one another through collaboration entries. That is, the detection modules trigger the application modules to perform certain operations through the track module. More specifically, the detection modules probe the link status, network performance and so on, and inform the application modules of the detection result through the track module. Upon aware of the changes of network status, the application modules deal with the changes accordingly to avoid communication interruption and network performance degradation. Track in the High Availability Configuration Guide Protection Switchover Technologies Protection switchover technologies aim at recovering network faults. They back up hardware, link, routing, and service information for switchover in case of network faults to ensure continuity of network services. See Table 1-3 for the details of protection switchover technologies. Table 1-3 Protection switchover technologies Technology Introduction Reference Active and Standby Switchover Ethernet Link Aggregation Smart Link MSTP RPR RRPP Devices supporting active and standby switchover are normally equipped with two main boards, with one being the active main board (AMB), and the other being the standby main board (SMB). The configurations on the SMB are the same as those on the AMB. When the AMB fails or is plugged out, the SMB automatically becomes the AMB to ensure non-stop operating of the devices. Ethernet link aggregation, most often simply called link aggregation, aggregates multiple physical Ethernet links into one logical link to increase link bandwidth beyond the limits of any one single link. This logical link is called an aggregate link. It allows for link redundancy because the member physical links can dynamically back up one another. Smart Link is a feature developed to address the slow convergence issue with STP. It provides link redundancy as well as fast convergence in a dual uplink network, allowing the backup link to take over quickly when the primary link fails. As a Layer 2 management protocol, the Multiple Spanning Tree Protocol (MSTP) eliminates Layer 2 loops by selectively blocking redundant links in a network, and in the mean time, allows for link redundancy. Resilient Packet Ring (RPR) is a new MAC layer protocol designed for transferring mass data services over MANs. It can operate on synchronous optical network/synchronous digital hierarchy (SONET/SDH), Dense Wavelength Division Multiplexing (DWDM) and Ethernet to provide flexible and efficient networking schemes for broadband IP MANs carriers. The Rapid Ring Protection Protocol (RRPP) is a link layer protocol designed for Ethernet rings. RRPP can prevent broadcast storms caused by data loops when an Ethernet ring is healthy, and rapidly restore the communication paths between the nodes in the event that a link is disconnected on the ring. Active and Standby Switchover in the High Availability Configuration Guide Ethernet Link Aggregation in the Layer 2 LAN Switching Configuration Guide Smart Link in the High Availability Configuration Guide MSTP in the Layer 2 LAN Switching Configuration Guide RPR in the High Availability Configuration Guide RRPP in the High Availability Configuration Guide 1-3

15 Technology Introduction Reference FRR GR NSR Stateful Failover VRRP Fast Reroute (FRR) provides a quick per-link or per-node protection on an LSP. In this approach, once a link or node fails on a path, FRR comes up to reroute the path to a new link or node to bypass the failed link or node. This can happen as fast as 50 milliseconds thus minimizing data loss. Protocols such as RIP, OSPF, IS-IS, static routing, and RSVP-TE support this technology. Graceful Restart (GR) ensures the continuity of packet forwarding when a protocol, such as BGP, IS-IS, OSPF, LDP, or RSVP-TE, restarts or during an active/standby switchover process. It needs other devices to implement routing information backup and recovery. Non-stop Routing (NSR) is a new feature used to ensure non-stop data transmission during an active/standby switchover. It backs up IP/MPLS forwarding information from the AMB to the SMB. Upon an active/standby switchover, NSR can complete link state recovery and route re-generation without requiring the cooperation of other devices. IS-IS supports this feature. Two devices back up the services of each other to ensure that the services on them are consistent. If one device fails, the other device can take over the services by using VRRP or dynamic routing protocols. Because the other device has already backed up the services, service traffic can pass through the other device, avoiding service interruption. Virtual Router Redundancy Protocol (VRRP) is an error-tolerant protocol, which provides highly reliable default links on multicast and broadcast LANs such as Ethernet, avoiding network interruption due to failure of a single link. Layer 3 IP Routing Configuration Guide, MPLS Configuration Guide/Configuration Guide of the corresponding protocols GR Overview in the High Availability Configuration Guide IS-IS in the Layer 3 IP Routing Configuration Guide Stateful Failover in the High Availability Configuration Guide VRRP in the High Availability Configuration Guide A single high availability technology cannot solve all availability problems in more and more complex network environments. Therefore, various availability technologies are required to enhance network availability on a basis of detailed analysis of network environments and user requirements. For example, at the distribution layer, a redundancy mechanism should be adopted on edge nodes to connect them to the corresponding nodes, and at the core layer, nodes should be meshed. Therefore, to achieve complete high availability, network designers and managers need to take into full consideration during the design, construction, and maintenance of a network. 1-4

16 2 Active and Standby Switchover Configuration Active and standby switchover is supported on the SR6608 only. This chapter includes these sections: Introduction to Active and Standby Switchover Active and Standby Switchover Configuration Task List Ignoring Version Check of the SMB Restarting the SMB Manually Performing an Active and Standby Switchover Displaying and Maintaining Active and Standby Switchover Introduction to Active and Standby Switchover If a device has two main boards, the main board that forwards and processes packets is called the active main board (AMB), and the main board that is in the standby state is called the standby main board (SMB). The SMB keeps its configuration the same as the AMB through the synchronization function. When the AMB fails, the SMB becomes the AMB to process services to ensure the normal operation of the device. This switchover process is called an active and standby switchover. Active and standby switchover functions in the following two ways: Automatic active and standby switchover. If the AMB fails or is plugged out, the system automatically performs an active and standby switchover to enable the SMB to function as the AMB. Manual active and standby switchover, that is, an active and standby switchover performed at the command line interface (CLI). For example, when you upgrade a device, you can upgrade the SMB first, and then perform an active and standby switchover to upgrade the AMB, thus to upgrade the entire device. This upgrade mode greatly reduces the interruption time of services. 2-1

17 . You cannot execute any command on the SMB, and you need to perform configurations at the command line interface on the AMB, which will synchronize the configurations to the SMB. Active and Standby Switchover Configuration Task List Task Remarks Ignoring Version Check of the SMB Restarting the SMB Manually Performing an Active and Standby Switchover Optional Optional Optional Ignoring Version Check of the SMB When the SMB is powered on, the system checks the versions of the AMB and SMB. If the versions of the AMB and SMB are not consistent, the SMB cannot be started. Follow these steps to disable the system from checking the version of the SMB: To do Use the command Remarks Enter system view system-view Ignore version check of the SMB ha slave-ignore-version-check Required Enabled by default. Restarting the SMB If the SMB fails, or is to being upgraded, you can restart the SMB to validate the newest version or configuration. However, you need to check the consistency of the versions of the AMB and SMB. If they are not consistent, configure to ignore version check of the SMB. To do Use the command Remarks Enter system view system-view Manually restart the SMB slave restart Required 2-2

18 When the SMB is restarted, the AMB performs initial synchronization on the SMB. During this process, the system does not respond to your input. After the initial synchronization is completed, you can execute all the configuration commands on the AMB and the AMB and SMB will keep a real-time synchronization process, meaning your configuration on the AMB will be copied to the SMB to ensure the consistency of the current configuration of the AMB and SMB. Manually Performing an Active and Standby Switchover To upgrade the AMB, restart the AMB. To avoid service interruption in this case, perform a manual active and standby switchover to enable the SMB to take over the AMB. To do Use the command Remarks Enter system view system-view Enable manual active and standby switchover Manually perform an active and standby switchover slave switchover { disable enable } slave switchover Optional Enabled by default Required The original AMB is restarted when an AMB and SMB switchover is performed. Therefore, ensure the consistency of the software version of the AMB and SMB before performing AMB and SMB switchover; if their software version is not consistent, you need to configure to ignore version check of the SMB first. Displaying and Maintaining Active and Standby Switchover To do Use the command Remarks Display the switchover state of the specified main board display switchover state [ slot slot-number ] Available in any view 2-3

19 3 Ethernet OAM Configuration H3C SR6602 routers do not support the Ethernet OAM feature. Distributed routers (all SR6600 routers but the SR6602) installed with high-density SAP interface modules support the Ethernet OAM feature. This chapter includes these sections: Ethernet OAM Overview Ethernet OAM Configuration Task List Configuring Basic Ethernet OAM Functions Configuring the Ethernet OAM Connection Detection Timers Configuring Link Monitoring Enabling OAM Remote Loopback Displaying and Maintaining Ethernet OAM Configuration Ethernet OAM Configuration Example Ethernet OAM Overview Background With features such as ease of use and low price, Ethernet has gradually become the major underlying technology for today s local area networks (LANs). Recently, with the emergence of Gigabit Ethernet and 10-Gigabit Ethernet, Ethernet is gaining popularity in metropolitan area networks (MANs) and wide area networks (WANs) as well. In the beginning, Ethernet is mainly used in LANs, which have low reliability and stability requirements. This is why an effective management and maintenance mechanism for Ethernet has been absent all along, hindering the usage of Ethernet in MANs and WANs. Implementing Operation, Administration and Maintenance (OAM) on Ethernet networks has now become an urgent matter. As a tool monitoring Layer 2 link status, Ethernet OAM is mainly used to address common link-related issues on the last mile. You can monitor the status of the point-to-point link between two directly connected network devices by enabling Ethernet OAM on them. Major Functions of Ethernet OAM Ethernet OAM can effectively promote your management and maintenance capabilities over Ethernet networks, guaranteeing the stability of the networks. Its major functions include: 3-1

20 Link performance monitoring: Monitors the performance indices of a link, including packet loss, delay, and jitter, and collects traffic statistics of various types. Fault detection and alarm: Checks the connectivity of a link by sending OAM protocol data units (OAMPDUs) and reports to the network administrators when a link error occurs. Remote loopback: Detects link errors by looping back non-oampdus. Ethernet OAMPDUs Ethernet OAM works on the data link layer. Ethernet OAM reports the link status by periodically exchanging OAMPDUs between network devices, so that the administrator can effectively manage the network. Figure 3-1 shows the formats of different types of OAMPDUs. Figure 3-1 Formats of different types of Ethernet OAMPDUs The fields in an OAMPDU are described as follows: Table 3-1 Description of the fields in an OAMPDU Field Dest addr Source addr Type Subtype Flags Code Description Destination MAC address of the Ethernet OAMPDU. It is a slow protocol multicast address 0180c As slow protocol packet cannot be forwarded by bridges, Ethernet OAMPDUs cannot be forwarded. Source MAC address of the Ethernet OAMPDU. It is the bridge MAC address of the sending side and is a unicast MAC address. Type of the encapsulated protocol in the Ethernet OAMPDU. The value is 0x8809. The specific protocol being encapsulated in the Ethernet OAMPDU. The value is 0x03. Status information of an Ethernet OAM entity. Type of the Ethernet OAMPDU Throughout this document, a port with Ethernet OAM enabled is called an Ethernet OAM entity or an OAM entity. 3-2

21 Table 3-2 shows the function of the three types of OAMPDUs. Table 3-2 Functions of different types of OAMPDUs OAMPDU type Information OAMPDU Event Notification OAMPDU Loopback Control OAMPDU Function Used for transmitting state information of an Ethernet OAM entity (including the information about the local device and remote devices, and customized information) to the remote Ethernet OAM entity and maintaining OAM connections Used by link monitoring to notify the remote OAM entity when it detects problems on the link in between. Used for remote loopback control. By inserting the information used to enable/disable loopback to a loopback control OAMPDU, you can enable/disable loopback on a remote OAM entity. How Ethernet OAM Works This section describes the working procedures of Ethernet OAM. Ethernet OAM connection establishment Ethernet OAM connection is the base of all the other Ethernet OAM functions. OAM connection establishment is also known as the Discovery phase, where an Ethernet OAM entity discovers remote OAM entities and establishes sessions with them. In this phase, interconnected OAM entities notify the peer of their OAM configuration information and the OAM capabilities of the local nodes by exchanging Information OAMPDUs and determine whether Ethernet OAM connections can be established. An Ethernet OAM connection can be established only when the settings concerning loopback, link detecting, and link event of the both sides match. After an Ethernet OAM connection is established, Ethernet OAM takes effect on both sides. The router operates in active or passive Ethernet OAM mode. Table 3-3 compares the two modes. Table 3-3 Active Ethernet OAM mode and passive Ethernet OAM mode Item Active Ethernet OAM mode Passive Ethernet OAM mode Initiating OAM Discovery Available Unavailable Responding to OAM Discovery Available Available Transmitting Information OAMPDUs Transmitting Event Notification OAMPDUs Transmitting Information OAMPDUs without any TLV Transmitting Loopback Control OAMPDUs Responding to Loopback Control OAMPDUs Available Available Available Available Available (if both sides operate in active OAM mode) Available Available Available Unavailable Available 3-3

22 OAM connections can be initiated only by OAM entities operating in active OAM mode, while those operating in passive mode wait and respond to the connection requests sent by their peers. No OAM connection can be established between OAM entities operating in passive OAM mode. After an Ethernet OAM connection is established, the Ethernet OAM entities on both sides exchange Information OAMPDUs at a specified interval (called a handshake packet transmission interval) to check whether the Ethernet OAM connection is normal. If an Ethernet OAM entity receives no Information OAMPDU within the Ethernet OAM connection timeout time, the Ethernet OAM connection is considered disconnected. Link monitoring Error detection in an Ethernet is difficult, especially when the physical connection in the network is not disconnected but network performance is degrading gradually. Link monitoring is used to detect and indicate link faults in various environments. Ethernet OAM implements link monitoring through the exchange of Event Notification OAMPDUs. Upon detecting a link error event listed in Table 3-4, the local OAM entity sends an Event Notification OAMPDU to notify the remote OAM entity. With the log information, network administrators can keep track of network status in time. Table 3-4 describes the link events. Table 3-4 Ethernet OAM link error events Ethernet OAM link events Errored symbol event Errored frame event Errored frame period event Errored frame seconds event Description An errored symbol event occurs when the number of detected symbol errors over a specific detection interval exceeds the predefined threshold. An errored frame event occurs when the number of detected error frames over a specific interval exceeds the predefined threshold. An errored frame period event occurs if the number of frame errors in specific number of received frames exceeds the predefined threshold. When the number of error frame seconds detected on a port over a detection interval reaches the error threshold, an errored frame seconds event occurs. The system transforms the period of detecting errored frame period events into the maximum number of 64-byte frames that a port can send in the specific period, that is, the system takes the maximum number of frames sent as the period. The maximum number of frames sent is calculated using this formula: the maximum number of frames = interface bandwidth (bps) errored frame period event detection period (in ms)/( ) If errored frames appear in a certain second, this second is called an errored frame second. Remote fault detection Information OAMPDUs are exchanged periodically among Ethernet OAM entities across established OAM connections. In a network where traffic is interrupted due to device failures or unavailability, the 3-4

23 flag field defined in information OAMPDUs allows an Ethernet OAM entity to send error information (the critical link event type) to its peer. In this way, you can keep track of link status in time through the log information and troubleshoot in time. Table 3-5 lists the critical link error events and the transmission frequencies of the corresponding OAMPDUs. Table 3-5 Critical link error events Type Description OAMPDU transmission frequencies Link Fault Peer link signal is lost. Once per second Dying Gasp Critical event An unexpected fault, such as power failure, occurred. An undetermined critical event happened. Non-stop Non-stop Remote loopback Remote loopback is available only after the Ethernet OAM connection is established. With remote loopback enabled, the Ethernet OAM entity operating in active Ethernet OAM mode sends non-oampdus to its peer. After receiving these frames, the peer does not forward them according to their destination addresses. Instead, it returns them to the sender along the original path. Remote loopback enables you to check the link status and locate link failures. Performing remote loopback periodically helps to detect network faults in time. Furthermore, performing remote loopback by network segments helps to locate network faults. Standards and Protocols Ethernet OAM is defined in IEEE 802.3h (Carrier Sense Multiple Access with Collision Detection (CSMA/CD) Access Method and Physical Layer Specifications. Ethernet OAM Configuration Task List Complete the following tasks to configure Ethernet OAM: Task Remarks Configuring Basic Ethernet OAM Functions Configuring the Ethernet OAM Connection Detection Timers Configuring Errored Symbol Event Detection Required Optional Optional Configuring Link Monitoring Configuring Errored Frame Event Detection Configuring Errored Frame Period Event Detection Configuring Errored Frame Seconds Event Detection Optional Optional Optional Enabling OAM Remote Loopback Optional 3-5

24 Configuring Basic Ethernet OAM Functions As for Ethernet OAM connection establishment, an Ethernet OAM entity operates in active mode or passive mode. Only an Ethernet OAM entity in active mode can initiate connection establishment. After Ethernet OAM is enabled on an Ethernet port, according to its Ethernet OAM mode, the Ethernet port establishes an Ethernet OAM connection with its peer port. Follow these steps to configure basic Ethernet OAM functions: To do Use the command Remarks Enter system view System-view Enter Ethernet port view interface interface-type interface-number Set the Ethernet OAM mode oam mode { active passive } Optional The default is active Ethernet OAM mode. Enable Ethernet OAM on the current port oam enable Required Ethernet OAM is disabled by default. To change the Ethernet OAM mode on an Ethernet OAM-enabled port, you need to first disable Ethernet OAM on the port. Configuring the Ethernet OAM Connection Detection Timers After an Ethernet OAM connection is established, the Ethernet OAM entities on both sides exchange Information OAMPDUs at a specified interval (called the handshake packet transmission interval) to check whether the Ethernet OAM connection is normal. If an Ethernet OAM entity receives no Information OAMPDU within the Ethernet OAM connection timeout time, the Ethernet OAM connection is considered disconnected. By adjusting the handshake packet transmission interval and the connection timeout timer, you can change the detection time resolution for Ethernet OAM connections. Follow these steps to configure the Ethernet OAM connection detection timers: To do Use the command Remarks Enter system view System-view Configure the Ethernet OAM handshake packet transmission interval Configure the Ethernet OAM connection timeout timer oam timer hello interval oam timer keepalive interval Optional 1000 millisecond by default Optional 5000 milliseconds by default 3-6

25 After the timeout timer of an Ethernet OAM connection expires, the local OAM entity ages out its connection with the peer OAM entity, causing the OAM connection to be disconnected. Therefore, you are recommended to set the connection timeout timer at least fives times the handshake packet transmission interval, thus ensuring the stability of Ethernet OAM connections. Configuring Link Monitoring After Ethernet OAM connections are established, the link monitoring periods and thresholds configured in this section take effect on all Ethernet ports automatically. Configuring Errored Symbol Event Detection An errored symbol event occurs when the number of detected symbol errors over a specific detection interval exceeds the predefined threshold. Follow these steps to configure errored symbol event detection: To do Use the command Remarks Enter system view system-view Configure the errored symbol event detection interval Configure the errored symbol event triggering threshold oam errored-symbol period period-value oam errored-symbol threshold threshold-value Optional 1 second by default Optional 1 by default Configuring Errored Frame Event Detection An errored frame event occurs when the number of detected error frames over a specific interval exceeds the predefined threshold. Follow these steps to configure errored frame event detection: To do Use the command Remarks Enter system view system-view Configure the errored frame event detection interval Configure the errored frame event triggering threshold oam errored-frame period period-value oam errored-frame threshold threshold-value Optional 1 second by default Optional 1 by default 3-7

26 Configuring Errored Frame Period Event Detection An errored frame period event occurs if the number of frame errors in specific number of received frames exceeds the predefined threshold. Follow these steps to configure errored frame period event detection: To do Use the command Remarks Enter system view system-view Configure the errored frame period event detection period Configure the errored frame period event triggering threshold oam errored-frame-period period period-value oam errored-frame-period threshold threshold-value Optional 1000 milliseconds by default Optional 1 by default Configuring Errored Frame Seconds Event Detection An errored frame seconds event occurs when the number of error frame seconds detected on a port over a detection interval exceeds the error threshold. Follow these steps to configure errored frame seconds event detection: To do Use the command Remarks Enter system view system-view Configure the errored frame seconds event detection interval Configure the errored frame seconds event triggering threshold oam errored-frame-seconds period period-value oam errored-frame-seconds threshold threshold-value Optional 60 second by default Optional 1 by default Make sure the errored frame seconds triggering threshold is less than the errored frame seconds detection interval. Otherwise, no errored frame seconds event can be generated. Enabling OAM Remote Loopback After enabling OAM remote loopback on a port, you can send test frames from the port to a remote port and then observe how many of these test frames are returned. In this way, you can calculate the packet loss ratio on the link, thus evaluating the link performance. Follow these steps to enable Ethernet OAM remote loopback: To do Use the command Remarks Enter system view System-view Enter Ethernet port view interface interface-type interface-number 3-8

27 To do Use the command Remarks Enable Ethernet OAM remote loopback oam loopback Required Disabled by default. Because enabling Ethernet OAM remote loopback impacts other services, use this function with caution. Ethernet OAM remote loopback is available only after the Ethernet OAM connection is established and can be performed only by the Ethernet OAM entities operating in active Ethernet OAM mode. Remote loopback is available only on full-duplex links that support remote loopback at both ends. Ethernet OAM remote loopback needs the support of the peer hardware. Enabling Ethernet OAM remote loopback interrupts data communications. After Ethernet OAM remote loopback is disabled, all the ports involved will shut down and then come up. Ethernet OAM remote loopback is disabled when you execute the undo oam enable command to disable Ethernet OAM, when you execute the undo oam loopback command to disable Ethernet OAM remote loopback, or when the Ethernet OAM connection times out. Ethernet OAM remote loopback is applicable to individual links only. It is not applicable to link aggregation member ports. In addition, you cannot assign ports where Ethernet OAM remote loopback is being performed to link aggregation groups. For more information about link aggregation groups, see Ethernet Link Aggregation in the Layer 2 LAN Switching Configuration Guide. Enabling internal loopback testing on a port during external loopback testing terminates the external loopback test. For more information about loopback testing, see Ethernet Interface in the Interface Configuration Guide. Displaying and Maintaining Ethernet OAM Configuration To do Use the command Remarks Display global Ethernet OAM configuration Display the statistics on critical events after an Ethernet OAM connection is established Display the statistics on Ethernet OAM link error events after an Ethernet OAM connection is established display oam configuration display oam critical-event [ interface interface-type interface-number ] display oam link-event { local remote } [ interface interface-type interface-number ] Available in any view Available in any view Available in any view 3-9

28 To do Use the command Remarks Display the information about an Ethernet OAM connection Clear statistics on Ethernet OAM packets and Ethernet OAM link error events display oam { local remote } [ interface interface-type interface-number ] reset oam [ interface interface-type interface-number ] Available in any view Available in user view Ethernet OAM Configuration Example Network requirements On the network shown in Figure 3-2: Enable Ethernet OAM on Router A and Router B to auto-detect link errors between the two routers. Monitor the performance of the link between Router A and Router B by collecting statistics about the error frames received by Router A. Figure 3-2 Network diagram for Ethernet OAM configuration Configuration procedure 1) Configure Router A # Configure GigabitEthernet 3/0/1 to operate in passive Ethernet OAM mode and enable Ethernet OAM for it. <RouterA> system-view [RouterA] interface gigabitethernet 3/0/1 [RouterA-GigabitEthernet3/0/1] oam mode passive [RouterA-GigabitEthernet3/0/1] oam enable [RouterA-GigabitEthernet3/0/1] quit # Set the errored frame detection interval to 20 seconds and set the errored frame event triggering threshold to 10. [RouterA] oam errored-frame period 20 [RouterA] oam errored-frame threshold 10 2) Configure Router B # Configure GigabitEthernet 3/0/1 to operate in active Ethernet OAM mode (the default) and enable Ethernet OAM for it. <RouterB> system-view [RouterB] interface gigabitethernet 3/0/1 [RouterA-GigabitEthernet3/0/1] oam mode active [RouterB-GigabitEthernet3/0/1] oam enable [RouterB-GigabitEthernet3/0/1] quit 3) Verify the configuration Use the display oam configuration command to display the Ethernet OAM configuration. For example: # Display the Ethernet OAM configuration on Router A. 3-10