Learning IOS and JUNOS

Introduction In multicast VLAN networks, subscribers to a multicast group can exist in more than one VLAN. If the VLAN boundary restrictions in a network consist of Layer 2 switches, it might be necessary to replicate the multicast stream to the same group in different subnets, even if they are on the same physical network. Multicast VLAN Registration (MVR) routes packets received in a multicast source VLAN to one or more receive VLANs. Clients are in the receive VLANs and the multicast server is in the source VLAN. Multicast routing has to be disabled when MVR is enabled. Refer to the configuration guide at Understanding Multicast VLAN Registration for more information on MVR. This document provides a simple topology: a stack of Catalyst 3750 Switches with multicast source/receivers connected to it, a working configuration, and output of commands to verify whether the MVR works or not when a stream is sending. Prerequisites Requirements There are no s...

MRM Multicast Routing Monitor (MRM) facilitates automated fault detection in a large multicast routing infrastructure. MRM is designed to alert a network administrator of multicast routing problems near to real-time. MRM has two components: MRM tester and MRM manager. MRM tester is a sender or receiver. MRM is available in Cisco IOS Software Release 12.0(5)T and later. Only the MRM testers and managers need to be running the MRM-supported Cisco IOS version. Test Sender Configuration interface Ethernet0 ip mrm test-sender Test Receiver Configuration interface Ethernet0 ip mrm test-receiver Test Manager Configuration ip mrm manager test1 manager e0 group 239.1.1.1 senders 1 receivers 2 sender-list 1 access-list 1 permit 10.1.1.2 access-list 2 permit 10.1.4.2 Output from the show ip mrm manager command on Test Manager is shown here: Test_Manager# show ip mrm manager Manager:test1/10.1.2.2 is not running Beacon interval/hold...

Pragmatic General Multicast (PGM) is a reliable multicast transport protocol for applications that require ordered, duplicate-free, multicast data delivery from multiple sources to multiple receivers. PGM guarantees that a receiver in the group either receives all data packets from transmissions and retransmissions or can detect unrecoverable data packet loss. There are no PGM global commands. PGM is configured per interface with the ip pgm command. You must enable Multicast routing on the router with PIM on the interface.

晚上閒來無事檢查一下e-mule的成果，看到了一份古早的multicast course slide + content的PDF，真的有點衝動想要把它整本印出來，裏面的內容真的很詳細很棒，但是現在完全沒有教這些來龍去脈，所以我想現在的學生就算是考過CCNP/CCIP對於multicast也只是一知半解。 在文章裏面我剛好看到了一個也出現在BSCI課文中的一個專有名詞 Designated Router/Querier，更重要的是…Cisco BSCI 教科書中那段文章還是錯的，它把highest IP寫成了lowest IP...(心中OS:習慣就好 習慣就好 教書教了三年還真的仍不習慣~) • Designated Router (DR) – For multi-access networks, a Designated Router (DR) is elected. In PIM Sparse mode networks, the DR is responsible for sending Joins to the RP for members on the multi-access network and for sending Registers to the RP for sources on the multi-access network. For Dense mode, the DR has no meaning. The exception to this is when IGMPv1 is in use. In this case, the DR also functions as the IGMP Querier for the Multi-Access network. • Designated Router (DR) Election – To elect the DR, each PIM node on a multi-access network examines the received PIM Hello messages from its neighbors and compares the IP Address of its interface with the IP Address of its PIM Neighbors. ...

相對於大家都很熟悉的指令 - 'ip igmp join-group'，這邊我要跟各位介紹一個不常使用到的指令 - 'ip igmp static-group' ip igmp static-group To configure static group membership entries on an interface, use the ip igmp static-group command in interface configuration mode. To delete static group membership entries, use the no form of this command. ip igmp static-group {* | group-address [source {source-address | ssm-map}] | class-map class-map-name} no ip igmp static-group {* | group-address [source {source-address | ssm-map}] | class-map class-map-name} Usage Guidelines Use the ip igmp static-group command to configure static group membership entries on an interface. When you configure the ip igmp static-group command, packets to the group are fast-switched out the interface, provided that packets were received on the correct reverse path forwarding (RPF) interface. Once configured, static group membership entries are added to the IGMP cache and mroute table. Configuring the ip igmp static-group command is u...

Dynamic Intra-AS RP assignments should not leak out to other service providers. (1)Auto-RP interface F0/0 ip multicast boundary 1 ! access-list 1 deny 224.0.1.39 access-list 1 deny 224.0.1.40 access-list 1 permit 224.0.0.0 15.255.255.255 (2)BSR interface F0/0 ip pim bsr-border

The Bootstrap Router (BSR) capability was added in PIM version 2. It automates and simplifies the Auto-RP process. It is enabled by default in Cisco IOS releases supporting PIMv2. There are interoperability and design issues with PIM v1. See the Configuration Guide for more advice on this. The short form of the advice is to set up your BSR to also be Auto-RP mapping agent, make sure all RP's run PIMv2, and then the PIM versions can interoperate. We'll assume you have upgraded your routers and all are running PIM v2. This means you'll have one active RP per multicast group, compared to several for the same group in PIMv1. You configure sparse-dense-mode on interfaces, since Sparse or Dense are now properties of a multicast group, not an interface. PIMv1 plus Auto-RP does the same tasks as BSR. But Auto-RP is Cisco proprietary, whereas PIMv2 with BSR is an IETF standards track protocol, which means it should interoperate with routers from other vendors. To use Bootstrap Route...

Auto-RP automatically distributes information to routers as to what the RP address is for various multicast groups. It simplifies use of multiple RP's for different multicast group ranges. It avoids manual configuration inconsistencies, and allows for multiple RP's acting as backups to each other. Cisco routers automatically listen for this information. Auto-RP relies on a router designated as RP mapping agent. Potential RP's announce themselves to the mapping agent, and it resolves any conflicts. The mapping agent then sends out the multicast group-RP mapping information to the other routers. How does it does this? It uses multicast to send the mapping information to the other routers! The specific groups used are 224.0.1.39 and .40. The first (.39) is used to advertise, the second (.40) is used for discovery. Of course, there's a chicken and egg problem there: how can you send out multicast information via multicast if the Auto-RP information is needed to make PIM-SM ...

這一個指令可能很少人知道，除非你已經準備CCIE Lab一陣時間，不然平時不太會使用到這個功能，好不容易才把它搞懂， 這個指令最重要的功能就是可以讓只支援sparse/bidirectional/ssm mode的interface利用dense mode的方式來flooding Auto-RP information，如果題目要求要使用Auto-RP但是不能使用ip pim sparse-dense-mode時，請記得這個指令的存在! To cause IP multicast traffic for the two Auto-RP groups 224.0.1.39 and 224.0.1.40 to be Protocol Independent Multicast (PIM) dense mode flooded across interfaces operating in PIM sparse mode, use the ip pim autorp listener command in global configuration mode . To disable this feature, use the no form of this command. Usage Guidelines Use the ip pim autorp listener command with interfaces configured for PIM sparse mode operation in order to establish a network configuration where Auto-RP operates in PIM dense mode and multicast traffic can operate in sparse mode, bidirectional mode, or source specific multicast (SSM) mode. Examples The following example enables IP multicast routing and the Auto-RP listener feature on a router. It also configures the router as a Candid...

這份文章的來源，如果各位曾經很認真讀過書的話，可能有印象，這是一個可以線上閱讀書本內容的網站，而我所摘錄的內容就是來自於Routing TCP IP Volume II CCIE Professional Development，這一個關於MSDP的說明我想對各位都蠻重要的，因為大部份的人都沒有使用過MSDP的經驗，但是如果要準備SP CCIE的Candidates就不得不認真學習一下了! ...(略) Operation of Multicast Source Discovery Protocol (MSDP) The purpose of MSDP is, as the name states, to discover multicast sources in other PIM domains. The advantage of running MSDP is that your own RPs exchange source information with RPs in other domains; your group members do not have to be directly dependent on another domain's RP. NOTE You will see in some subsequent case studies how MSDP can prove useful for sharing source information within a single domain, too. MSDP uses TCP (port 639) for its peering connections. As with BGP, using point-to-point TCP peering means that each peer must be explicitly configured. When a PIM DR registers a source with its RP as illustrated in Figure 7-8. the RP sends a Source Active (SA) message to all of its MSDP peers. Figure 7-8. RPs Adverti...

Anycast RP IP multicast is deployed as an integral component in mission-critical networked applications throughout the world. These applications must be robust, hardened, and scalable to deliver the reliability that users demand. Using Anycast RP is an implementation strategy that provides load sharing and redundancy in Protocol Independent Multicast sparse mode (PIM-SM) networks. Anycast RP allows two or more rendezvous points (RPs) to share the load for source registration and the ability to act as hot backup routers for each other. Multicast Source Discovery Protocol (MSDP) is the key protocol that makes Anycast RP possible. The scope of this document is to explain the basic concept of MSDP and the theory behind Anycast RP. It also provides an example of how to deploy Anycast RP. Multicast Source Discovery Protocol Overview In the PIM sparse mode model, multicast sources and receivers must register with their local rendezvous point (RP). Actually, the router closest to a source or a...

What is IGMPv1? IGMPv1使用Query-Response模型來允許Multicast Router和Multi-Layer Switch來確定在本網段內哪個Multicast Group是啟動的。在這個模型中，Router或Switch充當IGMP Querier，週期性(每隔60秒)地發送IGMPv1 Membership Query給224.0.0.1。啟用Multicast的所有主機監聽該位址並接收Query Packet。主機以IGMPv1 Membership Report回覆，表示它要接收特定Group的Multicast Traffic；該網段中的Router或Switch就可以了解Multicast Group中有哪些接收者。 主機可以通過發送一個或多個主動的Membership Report封包表明加入(Join)一個Multicast Group。如: 某個主機主動發送一個Report封包表明要接收Multicast Group(224.1.1.1)的流量。 主機通過停止處理Multicast Group Traffic以及不回應IGMP Query的方式來離開Multicast Group。 IGMPv1依靠L3的IP Multicast Routing Protocol(PIM、DVMRP等)來解決同一網段中哪個Router或Multi-Layer Switch成為Querier。Querier Router發送IGMPv1的Query來確定哪個Multicast Group是啟動的。通常Designated Router會被選擇為Querier。 IGMPv1的封包有2種： - Member Query(224.0.0.1, 每60秒查詢一次) - Member Report What is IGMPv2? IGMPv2的Query和Membership Report與IGMPv1類似。它們的差別在於： (一) IGMPv2的Query分為兩部分： - General Query(功能與IGMPv1的Query相同) - Group-Specific Query(僅查詢特定Group的資訊) (二) IGMPv1和IGMPv2的Membership Report使用不同的類型代碼。 IGMPv2的新特性包括： 1）Que...