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EOS Tricks and Tips That Make Life Easier

ContentsIntroductionOverviewNavigational TricksUsing “conf” at Any Hierarchical LevelAcceptance of CIDR NotationTab CompletionNo “do” is needed in config modeAdding “all” to your Show RunTroubleshooting TipsWatch DiffIsolating the most recent syslogsNetwork Visibility Analyzer or LANZGrepLinux access and Historical Show Techs Use of Linux to Help DebugEvent-monitorRelated references to check out Introduction Arista’s Extensible Operating System has several small features that make life in the CLI simpler, quicker, neater, and all-around just easier. Here are a few common practices which Arista’s Architects and TAC Engineers use with frequency. Overview While a plethora of different tricks and methods exist that make life simpler for network engineers,...
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CCF & DMF Interface Optics Troubleshooting

ContentsOverview1. Basic Layer 1 Troubleshooting2. HCL Compliant optics3. Dom Levels4. FEC (Forward error-correction) disable/Enable5. Optics pairing Overview Aside from the usual Layer 1 troubleshooting thats available, there are a few other steps  that can be taken to identify Layer 1 interface issues. 1. Basic Layer 1 Troubleshooting Please ensure you’ve completed the following Layer 1 troubleshooting before moving forward. That would include Reseating the optics Replacing the optics Moving the optics to another port on the switch Cleaning the cables/fiber Changing the cables Loopback testing Ensuring the port speed and optic types are the same 2. HCL Compliant optics The...
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EOS Logging Explained

  ContentsShow Logging ExplainedLogging LocationsBuffer LoggingConsole LoggingPersistent LoggingMonitor LoggingSynchronous LoggingTrap LoggingLogging OptionsSequence NumbersLogging FacilityHostname FormatRepeat Logging IntervalRepeat MessagesFacility ColumnSeverity vs. Effective Severity Column Show Logging Explained   What’s in a log? This document will serve to explain all of the available options and sub-feature explanations when it comes to logging. Each of the below sections correspond directly to the output of ‘show logging’ to attempt to explain each of them one by one.   switch#show log Syslog logging: enabled     Buffer logging: level debugging     Console logging: level errors     Persistent logging: disabled     Monitor logging: level errors     Synchronous logging: disabled     Trap logging: level...
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EVPN Multicast OISM Scenarios

ContentsObjectiveScenariosScenario 1TopologyVxlan ConfigurationBGP ConfigurationPoints to noteScenario 1: logical flowOutputs (show commands)Scenario 2TopologyVxlan and BGP configurationScenario 2: logical flowScenario 3: multicast source connected to external PIM domainTopologyScenario 3: logical flow with outputsScenario 4: both multicast source and receiver are in external PIM domain Objective The objective of this article is to understand how EVPN OISM (Optimised Inter Subnet Multicast) operates in certain scenarios/designs and understanding the logical flow. This article is best suited if you have already read the below TOI and have some trouble understanding how it would work in real world: https://eos.arista.com/eos-4-25-1f/multicast-evpn-irb/ Scenarios Scenario 1 Topology In above topology,...
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CCF/DMF Support Bundle

This article covers support bundle generation and tips on how to present the bundles to Arista Support for further analysis. Support bundles are a collection show,bash commands and logs in CCF (Converged Cloud Fabric) and DMF (Danz Monitoring Fabric). Formerly known as BCF and BMF respectively.   ContentsHow to collect a support bundleCLI CommandsGUIHow to upload a support bundleBCF>5.3, BMF>7.3: Use Direct Support Bundle UploadOptional: Enable Auto-UploadManually How to collect a support bundle CLI Commands From the CLI perspective, You can use the CLI command “Support” to generate the support bundle. BCF3-C1# support Generating diagnostic data bundle for technical support....
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TerminAttr – Manual Upgrade & Downgrade

ContentsIntroductionHow to check which version of TerminAttr is running on EOSWhen to upgrade/downgrade TerminAttr Manually Steps to UpgradeSteps to DowngradePossible Errors during downgrade Introduction TerminAttr is the EOS state streaming telemetry agent running as a single binary that can stream to both CloudVision and 3rd party applications using gNMI. It has been bundled with every EOS release from 4.17.0F and above and it’s also available as a SWIX extension that can be used to upgrade TerminAttr to the latest version. This article lists the steps to manually upgrade and downgrade TerminAttr from CLI. How to check which version of TerminAttr is...
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7500N Clearance Requirements and Footprint

ContentsIntroduction7500R/R2 Line Card ClearanceMax width (when ejector open and pull out line card) 7500R/R27500R3 Line Card ClearanceMax width (when ejector open and pull out line card) 7500R3References Introduction When install a 7500N chassis in a rack that provides adequate clearance for removing front and rear components. Arista 7500N Quick Start Guide states the Clearance requirements and footprint for switches.   7500R/R2 Line Card Clearance Since Quick Start Guide mentioned clearance is only for front and rear side, we added more clearance information here in the left and right space for 7500R/R2 Line card as below: Max width (when ejector open...
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VXLAN Configuration check using “show vxlan config-sanity”

ContentsIntroductionCLI DetailsVerificationLocal VTEP Configuration CheckRemote VTEP Configuration CheckPlatform Dependent CheckCVX Configuration CheckMLAG Configuration Check  Introduction Starting with EOS 4.22.0F, the show vxlan config-sanity command can be used to highlight various common errors in a VxLAN setup. This command is platform-independent. CLI Details switch# show vxlan config-sanity [ options ] VXLAN Config Sanity CLI has the following options. # show vxlan config-sanity (displays details for only FAIL and WARN checks) # show vxlan config-sanity brief (displays a brief output for FAIL and WARN checks) # show vxlan config-sanity detail (displays details for all checks) RESULT column may have one of these...
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High CPU on FHR or RP due to PIM

ContentsIntroductionOverviewBackgroundTroubleshooting Introduction High CPU due to PIM processes is not always a bug and may be caused by either a misconfiguration or a routing issue.  For the purposes of this document we will focus primarily on network misconfiguration. Overview Network wide choppy video, music on hold streams or loud speaker issues are commonly caused by multicast problems in the network.  Should the issue be network wide and not isolated to one area of the network, the next place to start looking is high CPU on the First Hop Routers (FHR) and/or the Rendezvous Point (RP).  When the CPU process is...
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GRE tunnel configuration – DMF/BMF

DMF support L2-GRE tunneling, to transmit/receive encapsulated monitoring traffic over a network. This feature can be used to extend a DMF deployment across multiple data centers or branch offices over networks connected by Layer 3 networks. This supports centralization or distribution of tools and taps/spans across multiple locations when they cannot be directly connected.   ContentsScenario 1: Using GRE tunnel as a core interface.Scenario 2: Using GRE tunnel as a delivery interfaceScenario 3: Using GRE tunnel as a filter interface. Scenario 1: Using GRE tunnel as a core interface. For core links, the direction of the tunnel should be bidirectional...
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CVP HA Deployment Guide

ContentsIntroductionScopeIn ScopeOut of ScopeDeployment ModelsCloudVision Virtual ApplianceCloudVision Physical ApplianceHigh AvailabilityClusteringBandwidth and Latency RequirementsInstallation RequirementsSingle-Site DeploymentMulti-Site DeploymentCentralised ClusterDual ClusterCold StandbyWarm StandbyBackup and RestoreDefault Backup ScheduleManual BackupManual RestoreAutomatic Backup ExportStreaming Telemetry to Multiple CVP ClustersShared Key Authentication ExampleCertificate-based Authentication ExampleProvisioning from Multiple ClustersSynchronize the Provisioning Dataset Introduction This document describes high availability deployment scenarios and best practices for Arista CloudVision Portal (CVP). The guide is intended for network architects and engineers who are planning, designing, or implementing an on-premises deployment of CVP. Scope In Scope CVP version 2020.2.x/2020.3.x/2021.1.x On-premises deployment CVP virtual appliance CVP physical appliance Single-site Multi-site Disaster recovery Out of...
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Use cases for CCF vCenter integration

ContentsOverviewSupported CasesUnsupported CasesValidation Overview This article will describe some supported and unsupported scenarios for interface-group creation on Converged Cloud Fabric (CCF) based on NIC teaming and load balancing policy used on the vCenter side.  It is applicable for Converged Cloud Fabric (CCF) deployments using vCenter integration. Following NIC teaming policies are supported on the vCenter side: Routing based on IP hash Source MAC hash Originating virtual port Explicit failover order  Routing based on physical NIC load. The teaming policies will be broadly classified as either IP-hash (Route based on IP hash) or non-IP-hash policies (remaining 4 policies) on the CCF...
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Vxlan Trident L2-Uplink Limitation 113722

If you’ve tried implementing VXLAN on Trident VTEPs with a Layer-2 uplink to remote-vteps, you may have noticed that sometimes packets can’t be successfully forwarded across the VXLAN fabric, or perhaps the latency observed is higher than what’s expected. Alternatively, maybe you never noticed the above symptoms and are here instead because you noticed the following log in your switch: STRATA-6-VXLAN_PORT_TO_NEXTHOP_OVERFLOW. These are the most common observations made when a Trident switch has hit the following limitation, 113722, found in EOS Release Notes: ContentsLimitations and Restrictions in 4.26.1F7300X3, 7320X, 7368, CCS-720XP, CCS-750, DCS-7010, DCS-7050X, DCS-7050X2, DCS-7050X3, DCS-7060X, DCS-7060X2, DCS-7060X4, DCS-7250X,...
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DMF Upgrade procedures 7.x.x+

ContentsDMF Upgrade ProceduresOverviewSwitch/Node upgradesSteps for Upgrading Controllers 7.x.x to 8.x.xCopying Upgrade image to controllerOption 1Option 2Controller upgradeAnalytics and Recorder Nodes DMF Upgrade Procedures Overview This Document will provide the necessary steps to upgrade DMF and its respected nodes individually from 7.x.x onward. These upgrade steps are also present in the DMF deployment guide, starting on chapter 6. https://www.arista.com/en/support/software-download Switch/Node upgrades After the controllers have upgraded, the switches will automatically reboot to upgrade. Service nodes, starting from 7.x.x, will upgrade automatically similarly to fabric switches. Analytics and Recorder nodes need to be upgraded separately, which will be covered later in this...
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DMF Downgrade/ Fresh Install

ContentsDMF Downgrade/ Fresh InstallIDRAC Fresh InstallBooting with Alternate Partition DMF Downgrade/ Fresh Install   Please be advised downgrading of DMF version image using the “upgrade launch” procedure is not supported. There are 2 ways to perform the downgrades. Loading the alternate boot partition which consists of the previous DMF version image or doing a fresh install via IDRAC. IDRAC Fresh install may be used when you don’t have the previous DMF image on the alternate partition. IDRAC Fresh Install Using IDRAC we can perform a fresh install of the ISO on a device. The process is the same for Controller...
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BFD troubleshooting tips

ContentsBFD quick introduction:Troubleshooting BFD commands:Troubleshooting steps:1) BFD goes down because of underlying physical interface going down:2) If bfd packets are blocked by any ACLs3) Check if bfd packets are sent and received properly4) In the above cases, the problem is live. But what if the problem is intermittent and bfd session goes down at unpredictable times. 5) BFD packets are sent properly but the session still goes down. 6) QOS settings: BFD quick introduction: What is BFD? Bidirectional Forwarding Detection(BFD) is a low overhead protocol designed to provide rapid detection of failures in the path between adjacent forwarding engines over any media...
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Setting up AD, NPS, and RADIUS authentication using Windows NPS

ContentsOverviewDefinitionLab SetupConfiguring Windows NPS and ADAdding Users and Groups to ADRADIUS Server configurationConfiguring NPS policiesConfiguring the Arista SwitchSetting up CVP to authenticate users using RADIUS Overview This article will guide through setting up Network Policy Server (NPS) on a Windows Server along with Active Directory Domain Services (AD DS). In addition, this document will address the required parameters to successfully authenticate users to login into Arista switches and CVP using RADIUS. Definition Network Policy Server (NPS) – This feature allows administrators to define policies for Network access authentication, authorization and accounting for wireless, authenticating switch, and remote access dial-up, and...
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Extending EVPN and VXLAN to the Host

ContentsOverviewGoalsTopologySoftware VersionsConfigurationSpine Configuration (route server)Leaf-1a/b ConfigurationHost ConfigurationLinuxFRRTestingTroubleshootingChecking the EVPN peering and routes on the spines/route-serversChecking FRRChecking that FRR has correctly provided the information to the kernelCaveatsAlternative Configuration Options Overview VxLAN provides a highly scalable, standards based approach for constructing L2 overlays on top of routed networks. It is defined in RFC7348, and encapsulates the original host Ethernet frame in a UDP + IP + Ethernet frame. BGP EVPN (RFC 7432 and RFC 8365 for its application to VXLAN) is a standards based control protocol to efficiently discover other endpoints (VTEPs) and distribute reachability information (MAC addresses). This post assumes the reader is...
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Recommended Configurations for Multicast Using Anycast-RP

ContentsOverviewUse CasesTroubleshooting Steps Overview Multicast is a means of sending data from one source to many receivers.  To understand what one to many looks like no further than a TV streaming service and or a paging system which calls only certain phones.  Unlike broadcast which multicast may act like depending on the design, typically multicast packets are not meant for the whole network but to a set of end points for a specific group.  Sending to a group is achieved by sending data to a multicast IP whose range is from 224.0.0.1 to 239.255.255.255.   For data to flow from its...
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Using the CloudVision API with Service Accounts

ContentsDescriptionPlatform CompatibilityHow TocURLPythoncvpracrequestsAdditional Resources Description With the release of CloudVision Portal 2020.3, you have the ability to create Service Accounts. I won’t show you how to create a Service Account, but you can go to this TOI to read about that. This article will show you how to use Service Account Tokens in Python and cURL for API calls. Platform Compatibility This applies to both CVaaS and on-premise installations. How To Using a Service Account Token allows you to bypass the standard authentication process when making API calls. It also allows you to create a local “account” on CloudVision that doesn’t...
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