• Tag : Multicast


Curl’ing with EOS and third party devices

Perhaps you’re aware that EOS is based on Linux, which comes with many powerful & useful built-in utilities. I recently wrote an EOS Central article on sed. Even if you are not a pure networking person (perhaps you’re a server person), many of the familiar Linux tools you have used in your past exist on EOS natively today. One of my customers recently shared an experience with me that made me smile because they had now started to embrace the Linux underpinnings & power of EOS after running into a configuration challenge with a 3rd party (television) broadcast IP/SDI gateway...
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Support for multicast (S,G) counters

Description The multicast route counters count packets and bytes per group, source and vrf  Every multicast route will be counted when the feature is turned on if there are sufficient hardware counter resources available. As there is a limited number of hardware counter resources, selected multicast routes can be “prioritized” in order to provide them the needed hardware counter resources over the “non-priority” multicast routes in case of resource contention. Priority multicast routes can be configured if: Hardware counter resources are available: The priority multicast routes do not affect the existing non-priority multicast route counters. In case there are insufficient...
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Support for Multicast NAT

Description Multicast NAT is a feature that performs NAT translations on multicast traffic. The following multicast features are supported: Source Static NAT on egress interface Destination Static NAT on ingress interface Twice Static NAT on egress interface Can be enabled on SVI, VLAN, and Port Channel. Platform Compatibility CCS-720XP-24ZY4 CCS-720XP-24Y6 CCS-720XP-48Y6 CCS-720XP-48ZC2 DCS-7050SX3-48YC12 DCS-7050TX3-48C8 DCS-7050CX3M-32S DCS-7050CX3-32S DCS-7050SX3-48YC8 DCS-7050SX3-48C8 Configuration Configuration of Multicast NAT is similar to the existing NAT CLI configuration commands. Below are sample configurations for setting up static multicast NAT translation. 1) Twice NAT on egress interface Ethernet8 for multicast traffic coming from host ingressing on...
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Support for IPv6 multicast (S,G) counters

Description The IPv6 multicast route counters count packets and bytes per group, source and vrf  Every IPv6 multicast route will be counted when the feature is turned on if there are sufficient hardware counter resources available. As there is a limited number of hardware counter resources, selected IPv6 multicast routes can be “prioritized” in order to provide them the needed hardware counter resources over the “non-priority” IPv6 multicast routes in case of resource contention. Priority IPv6 multicast routes can be configured if: Hardware counter resources are available: The priority multicast routes do not affect the existing non-priority multicast route counters....
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Multicast Monitoring in CVP

Hi all, is there any way inside CVP to have a visual (table, graph, etc..) of the multicast flow, for example have a list of all multicast group and, for each group, details as: switch, position (Ingress, Egress, Core) and bitrate on the involved interfaces? Thanks! Andrea

Fastdrop static

Description Fastdrop static is a feature that allows the static multicast routing agent to respond to cache miss messages and dynamically create fastdrop routes. For 7280R/7500R based platforms, when multicast routing is enabled on an interface an mroute is needed to forward traffic to L3 and L2 OILs as the platform can only do S, G lookup or EthGroup lookup, not both. With dynamic multicast routing, this is taken care of by the PIM agent. The use case for this feature is when static multicast routing is being used, but there are not static mroutes for all S,Gs. If traffic...
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Multicast multipath router-ID (IPv4)

Description This feature provides multipath router-id, a new multipath mode to control the behavior of RPF selection. In the default multipath mode, it is possible that downstream Pim neighbors will select as RPF different upstream Pim neighbors despite having the same ECMP routes to the source. This may have the undesirable effect that the source has to deliver to multiple upstream Pim neighbors instead of one. When multipath router-id is configured, traffic for a group or source-group will be routed through only one upstream PIM neighbor for all downstream PIM neighbors given that these neighbors have the same ECMP routes...
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Tap Aggregation PTP Sync & Transparent Clock (TC) PTP Multicast Configuration

 Description This article covers the configuration required to run the PTP TC with multicast transport environment, and Tap Aggregation DUT time sync with PTP GM. Platform Compatibility DCS-7020 DCS-7280SE/ DCS-7500E DCS-7280R/RX DCS-7500R/RX DCS-7150 DCS-7050X/XX DCS-7060X/XX Topology Diagrams     Configuration In this PTP implementation example, the NY1 will act as BC and NY4 as GM. Both are configured as PTP BC clocks but NY4 due to its lower Priority1 value will win the BCMA election and becomes the master. The NY2 and NY3 are configured as E2E TC clocks and will require PIM to forward the PTP messages generated by...
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IGMP Host-proxy

Interfaces on the switch can be configured to serve as IGMP host proxies. An IGMP host proxy exchanges IGMP reports (joins/leaves) between networks whose connection does not support PIM along network boundaries. Let’s take the example shown below: The customer network connects to the sender network through the edge switch’s Ethernet 1 interface, which is configured as an IGMP host proxy. PIM is enabled within the publisher and customer networks but not on the connection between the networks.   When only “ip igmp host-proxy” is configured on the interface, IGMP reports will be sent for any (*,G) or (S,G) entry...
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Pim SSM IPV4 Non-DR OIF Installation for Fast Failover

Description In a Mlag setup with Pim SSM, one peer becomes the DR for a layer 3 interface and is responsible for routing multicast traffic on that interface. If this DR fails, the other peer, who was originally non-DR but becomes the new DR, may need to establish  SPT trees to get the multicast traffic or at the very least, add interfaces to OIF list of many multicast routes. This can be very disruptive to multicast traffic flow if there are thousands of routes.  This feature “Pim SSM Non-DR OIF Installation” helps to reduce convergence times and decrease traffic loss...
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Enable source specific multicast

We currently have a querier (v3) running on VLAN 400 and it perfectly works for multicast group joins within that VLAN. However when performing a source specific group join it seems to forward traffic from other sources as well. My transmitting part is sending on group with source address My receiving part is subscribed to group with source address There is not multicast traffic to group from source; Expected result is that no multicast packets would be received, but it receives all traffic from What configuration is required to enable source specific multicast...
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Multicast forwarding using BESS (MFA)

Description The PIM routing protocol builds multicast routing state based on control packets and multicast data events. In our current implementation, we rely on the Linux kernel to notify the PIM agents regarding the multicast data events. Also, the Linux kernel forwards a multicast data packet before hardware gets programmed to do so. As an alternative to the Linux kernel, Multicast Forwarding based on BESS ( Berkeley Extensible Soft Switch ), MFA, can be used to generate multicast data events and forward multicast data packets. As the first release of MFA, it is officially supported for IPv6 PIM SSM. Although...
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IPv6 support for PIM source specific multicast

Description This feature adds support for PIM-SSM ( Source Specific Multicast ) for IPv6 Multicast Routing on platforms listed below. The TOI for the support in earlier versions/platforms is available here. Reference TOI for support of IPv6 Multicast Routing support is available here. Basic configuration commands can be found in the aforementioned TOI for enabling Ipv6 multicast routing Platform compatibility The following platforms are supported from software version 4.22.0 DCS-7050QX, DCS-7050SX, DCS-7050TX DCS-7050QX2, DCS-7050SX2, DCS-7050TX2 DCS-7050CX3, DCS-7050SX3 DCS-7060CX, DCS-7060CX2, DCS-7060SX2 DCS-7260CX, DCS-7260CX3, DCS-7260QX DCS-7300X, DCS-7300X3 series Show Commands The below commands can be leveraged in order to view the multicast...
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Introduction to IPv6 Multicast-Routing

Overview IPv6 multicast routing protocols are used to distribute ipv6 datagrams to one or more recipients. IPv6 PIM builds and maintains multicast routing using reverse path forwarding (RPF) based on unicast routing table. IPv6 PIM is protocol-independent and can use routing tables consisting of OSPFv3, IPv6 BGP or static routes, for RPF lookup. MLD is used to discover multicast hosts and maintain group membership on directly attached link. IPv6 multicast-routing has been introduced in the 4.21.0F release and is supported on 7280R and 7500R. Source-specific multicast (SSM) is currently supported on L3 routed port. PIM Sparse Mode In PIM-SM, each...
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Multicast in VXLAN with BGP EVPN control-plane

 Hello, We are trying to run multicast in data center overlay network. In our data centers we are using L3 leaf-spine topology with VXLAN. For the control plane BGP EVPN is used.  Leaf switches are deployed in an MLAG configuration. We want to run multicast between hosts that are on same vlan across switches in different MLAG domains. Multiple multicast receivers, as well as multiple senders are connected to different MLAG domains and are all in the same VLAN. Multicast receiver can receive m-c stream from the sender if both of them are in the same MLAG domain. But if receiver is connected to...
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Alert for multicast routing table overflow?

I have a customer with an Arista-DCS-7150S-52-CL-R running 4.15.9M code.  They have a fairly complex set of hosts and a large number of multicast groups.  Occasionally, one host will become deaf to a group.  A “netstat -ng” on the host indicates that the operating system still thinks it is subscribed to the group. Is there any way to determine if the routing table is overflowing and multicast routes are being trimmed?  Or if other limited multicast resources are being exhausted? I suspect the solution is to reduce the number of multicast groups being used, but we would like to determine the root...
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Wireless Network Optimization – Multicast Control Using Internet Group Membership Protocol (IGMP)

Introduction Multicast is often used to stream video. Multicast packets need to flood the network to reach the recipients, which means that these packets are forwarded to many network segments even though there may not be any clients on the segment that are interested in the video stream. A protocol was developed to cull this unwanted data, called Internet Group Membership Protocol (IGMP). IGMP provides a way for a client to inform another Layer 2 device that it wants to receive a multicast stream. It does this by sending an IGMP Report with the multicast address of the session it...
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Enabling Passive/Transparent Devices for PTP Multicast Routing

Why is PTP Multicast Routing Needed? PTP is a highly precise time protocol, the best practice for PTP is to introduce devices as PTP-Transparent (vs Passive) if the device is L3 and does not act as Boundary Clock. Any introduction of PTP-Passive devices in the path reduces the accuracy of the protocol. Both Transparent and Passive devices require additional configuration in order to forward the PTP stream. If a device must also manage a control-plane flow (and hence has a dependency on the control traffic), this can also reduce the accuracy of PTP.  Due to this, and as the capability for a...
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MBR (Multicast Border Router)

Intro Enabling PIM MBR on an interface (where we don’t have an upstream PIM neighbor) will allow multicast traffic from remote sources that are outside of our PIM domain to be treated as locally connected sources. We typically see this scenario when we are receiving multicast feeds from a remote Exchange and a PIM neighbourship is not established on our upstream links. In the current PIM implementation (EOS 4.14.0F and later) EOS will drop multicast traffic that is not considered to be locally connected by default and we need to configure MBR to allow this multicast data. In the interfaces...
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