• Tag : VXLAN


Problem with EVPN type-5 packet forwarding on vEOS

Hello, I am testing a solution based on VXLAN EVPN, with Type-5 routes, with vEOS, but I am having some issues in packet forwarding. The routes are correctly propagated, but when I try to ping from a device connected to one node, on a device connected to another node, the ping does not work. I also tried a ping, with a forced source IP, from the vEOS machine itself, but it has problems too. LEAF-2 LEAF-2#sh ip route vrf gold VRF: gold Codes: C – connected, S – static, K – kernel, O – OSPF, IA – OSPF inter...
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Description Starting with EOS release 4.22.0F, the EVPN VXLAN L3 Gateway using EVPN IRB supports routing traffic from IPV6 host to another IPV6 host on a stretched Vxlan VLAN. This TOI explains the EOS configuration and show commands. Platform Compatibility Platform supporting ND Proxy and ND Suppression DCS-7280R/7280R2 DCS-7050CX3-32S-F DCS-7050SX3-48YC12-F ( Starting in 4.22.1F ) DCS-7050SX3-48YC8 ( Starting in 4.22.1F ) DCS-7050/7050X/7050X2 ( Starting in 4.22.1F ) DCS-7260X/7260X3 ( Starting in 4.22.1F ) DCS-7060X/7060X2 ( Starting in 4.21.1F ) DCS-7250 ( Starting in 4.22.1F ) DCS-7300/DCS-7320 ( Starting in 4.22.1F ) Platform not supporting ND Proxy, No ND Suppression  DCS-7020R...
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VXLAN Auto Flood-List Construction

Description VXLAN flood-lists are typically configured via CLI or learned via control plane sources such as EVPN. The introduction of wireless access points (APs) into the VXLAN data-plane and the desire to minimize AP configuration led to the introduction of a new feature to learn VXLAN flood-lists via the data-plane. When a VXLAN packet is received from a remote VTEP on a new VNI, that remote VTEP is added to the flood-list for that VNI. When all of the MACs behind a remote VTEP have aged out or been removed, that remote VTEP is no longer considered active and it...
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EVPN Control Plane Support for MSS

Description This feature enables support for Macro Segmentation Service (MSS) to insert security devices into the traffic path for VXLAN networks using an EVPN control plane. With this feature enabled, CVX will continue to monitor the network via NetDB state and will initiate intercept and offload rules. With this feature enabled, MAC and IP reachability information will be learned and distributed in user configured L2 domains via EVPN.   CVX will continue to use the Vxlan Controller Service to discover network state and distribute MAC reachability information in service L2 domains (MSS L2 only.) Platform Compatibility Platform Independent (Subject to...
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EVPN – MLAG single homed hosts

Description As described in the Multi-VTEP MLAG TOI, singly connected hosts can lead to suboptimal peer-link utilisation. By adding a local VTEP to each MLAG peer, the control plane is able to advertise singly connected hosts as being directly behind a specific local VTEP / MLAG peer. The multi-VTEP MLAG feature has been extended to add EVPN control plane support. VXLAN bridging (EVPN Type-2 and Type-3 routes) and routing (EVPN Type-5 routes and IRB) are supported by this feature. When multi-VTEP MLAG mode is enabled, outgoing EVPN route advertisements will contain a nexthop and router MAC extended community as summarized...
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attached-host routes and MLAG

I have been experimenting in our test environment with attached-host routes on a vxlan network. We have are using asymmetric IRB across our vxlan infrastructure as it is (for the moment at least) simple enough for this not to cause us an issue. We want to use attached-host to ensure that the correct pair of leaf switches are used for routing “southbound” traffic. In the production environment there will be 5 pairs of leaf switches which will be routing traffic for the edge vlan. Behind this vlan are ~50 nodes that are connected with MLAG to the pairs of (7060CX)...
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SSU support for L2 EVPN with VXLAN

Description Smart System Upgrade (SSU) aims to minimize traffic loss during a software upgrade. The Smart System Upgrade (SSU) process includes the core functionality of Accelerated Software Upgrade, plus additional optimizations that permit a hitless restart of several features. SSU leverages protocols capable of graceful restart to minimize traffic loss during upgrade. For protocols not capable of graceful restart, SSU generates control plane messages and buffers them in hardware to be slowly released when the control plane is offline. Additionally, under SSU, the forwarding ASIC does not get reset and ports do not flap. Starting EOS 4.22.1F SSU is now...
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EVPN mutlihoming w/ ESI

I stumbled upon this archived [post](https://www.reddit.com/r/Arista/comments/azubnz/mlag_or_esi/) while researching EVPN support specifically on the EVPN multihoming side using common ESIs to extend beyond 2 switches in a LAG. Also this is the only post I’ve found mentioning EVPN Multihoming – https://eos.arista.com/arista-layer-2-vtep-evpn-vxlan-route-type-1-support/ but is limited to using mlag only. Does anyone have any information on when there will be support for the EVPN ESI LAGs?

VxLAN VTEP and VNI Counters

Description The VxLAN VTEP and VNI counters feature allows the device to count VxLAN packets received and sent by the device on a per VTEP and per VNI basis. Specifically, it enables the device to count bytes and packets that are encapsulated and decapsulated as they are passing through. The counters are logically split up in the two VxLAN directions:  “encap” counters count packets coming from the edge, encapsulated on the device and directed to the core, while “decap” counters count packets coming from the core, decapsulated on the device and heading towards the edge. To be able to count...
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“ip address virtual” support for PIM and IGMP

Description 4.22.1F introduces support for ip address virtual for PIM and IGMP in MLAG and Vxlan. On a VLAN, the same IP address can be configured using ip address virtual on both mlag devices as well as on different VTEPs. Control packets are source NATed by the kernel to a chosen IP address. The source NATing fails for PIM and IGMP. To overcome this, users can configure pim ipv4 local-interface and borrow the IP address to be used on the VLAN.  PIM and IGMP bypass the source NATing in the kernel. The interface configuration pim ipv4 local-interface allows PIM and...
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Description The “vxlan bridging vtep-to-vtep” feature allows VXLAN encapsulated packets ingressed at an Arista switch from a remote VTEP to be bridged and tunnelled back to the same or another remote VTEP. In a traditional VXLAN deployment, all VTEPs are connected to each other in a full mesh topology. So, whenever our switch receives a VXLAN packet from a remote VTEP that needs to be bridged, we never send that packet back through a VXLAN tunnel to another remote VTEP. This is done to prevent loops in general VXLAN networks where all remote VTEPs are reachable from one another. In...
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Does 7050SX support L3 vxlan evpn?

I am not able to import evpn from bgp vrf configuration on 7050SX, but able to do same on 7280R2. 7050SX-2(config-router-bgp-vrf-backup-tenant)#route-target import ? ASN(asplain):nn or ASN(asdot):nn or IP-address:nn Route Target Do you mind confirm that whether 7050SX support l3 evpn? Thank you!

EVPN VXLAN All-Active Multihoming

Description Ethernet VPN (EVPN) networks normally require some measure of redundancy to reduce or eliminate the impact of outages and maintenance. RFC7432 [1] describes four types of route to be exchanged through EVPN, with a built-in multihoming mechanism for redundancy. Prior to EOS 4.22.0F, MLAG is available as a redundancy option for EVPN with VXLAN, but not multihoming. EVPN multihoming is a multi-vendor standards-based redundancy solution that does not require a dedicated peer link and allows for more flexible configurations than MLAG, supporting peering on a per interface level rather than a per device level. It also supports a mass...
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Description Starting with EOS release 4.22.0F, the EVPN VXLAN L3 Gateway using EVPN IRB supports routing traffic from IPV6 host to another IPV6 host on a stretched Vxlan VLAN. This TOI explains the EOS configuration and show commands. Platform compatibility Platform Supporting ND Proxy and ND Suppression DCS-7280R/7280R2 DCS-7050CX3-32S-F DCS-7050SX3-48YC12-F ( Starting in 4.22.1F ) DCS-7050SX3-48YC8 ( Starting in 4.22.1F ) DCS-7050/7050X/7050X2 ( Starting in 4.22.1F ) DCS-7260X/7260X3 ( Starting in 4.22.1F ) DCS-7060X/7060X2 ( Starting in 4.21.1F ) DCS-7250 ( Starting in 4.22.1F ) DCS-7300/DCS-7320 ( Starting in 4.22.1F ) Platform Compatibility (No ND Proxy, No ND Suppression) DCS-7020R...
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VxLAN troubleshooting guide

VxLAN Basic Troubleshooting Guide I. Objective Provide basic/generic troubleshooting steps to customers in case any VxLAN issue is encountered in their network. II. Introduction: Troubleshooting VxLAN involves few steps as mentioned in the upcoming sections of this document. The below referred topology includes VxLAN configurations with server 1,2,3 as the host devices which obtain connectivity over a vxlan tunnel. Troubleshooting steps are bifurcated into routing and bridging to include multiple scenarios possible.   III. Topology   IV. Generic Configurations to be checked A. On the VTEPS check for the following configurations: #show run sec vxlan interface Vxlan1 vxlan source-interface Loopback1...
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BGP Crashing with VXLAN EVPN

I have a network setup with 6 Arista 7050QX running VXLAN-EVPN. All nodes are doing eBGP. I can establish eBGP sessions and configure EVPN as well but the moment I start sending traffic via VXLAN then BGP stops working saying “BGP agent not running”. I have tried 4.21.5F, 4.21.3F and currently using 4.20.5F but same result. Config looks like this at one end. Router bgp 65001 vlan 101 rd route-target both 101:10000002 redistribute learned interface Vxlan1 description VXLAN Interface vxlan source-interface Loopback0 vxlan udp-port 4789 vxlan vlan 100 vni 10000001 vxlan vlan 101 vni 10000002 Arista DCS-7050QX-32-R Hardware version:...
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MAC Address flapping – VXLAN with MLAG

As per the attached diagram, its a VXLAN EVPN setup. Everything was working fine on that side. Both switches in city A and City B have MLAG configured with the TOR Stack switches. After creating MLAG with the TOR Stack switches, all MAC addresses have started flapping. For example MAC address ab-bc-cd is coming from the server connected to TOR Stack switch in City B. On B-SW01 it is learning from Port-channel10 (MLAG) but on B-SW02 it is learning from VX1 interface (vxlan) which is coming from the RR via B-SW01 and then it hands it back to the TOR...
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EVPN MLAG Shared Router MAC

Description “MLAG Domain Shared Router MAC” is a new mechanism to introduce a new router MAC to be used for MLAG TOR Leaf pairs.  The user can have either explicitly configured MAC address of their choice or use the system generated MLAG system-id for this purpose.   When the MLAG shared MAC is set as the MLAG system ID value, the new shared MAC has the following properties: Unlike the bridge MAC which is different on each peer, this MLAG Domain shared router MAC has the same exact value on MLAG peers forming the same MLAG domain. This new shared...
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VXLAN Static and EVPN Dual Configuration

Description Configuration of VXLAN overlay using EVPN allows for extension of Layer-2 (L2) or Layer-3 (L3) networks across multiple data centers. VXLAN is configured on Provider Edge (PE) switches to create an overlay network to tunnel customer traffic between networks connected to the PE switches, while EVPN acts as the control plane by advertising reachability amongst the PE switches via EVPN route types 1-5. In some scenarios, one or more of the PE switches facing the customer network may not support EVPN. For example, the PE switch may be a Linux-based software VTEP (VXLAN Tunnel End-Point) running on a server...
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Layer 2 Data Center Interconnect – Reference Designs

Introduction VxLAN is a popular choice for extending Layer 2 both intra and inter DC using overlays. Arista offers multiple control plane choices for VxLAN: Static HER, CVX and EVPN. In this article, two approaches to designing a L2 DCI over a L3 underlay are discussed. High-level technical details of each design approach is described first, followed by a comparison of the two options along with their typical use cases. Design 1: Multi-domain Overlay In this design, two overlay domains are identified: DC Fabric domain: This is the VxLAN domain within the DC Layer 3 Leaf-Spine Fabric with Leafs acting...
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