• Author : josh


Latency Analyzer (LANZ) Architectures and Configuration

Introduction   Arista Latency Analyzer, or LANZ, is a technology that tracks and logs buffer congestion and latency in real time.  The visibility provided by LANZ of network hot-spots and microburst oversubscription gives the network operator greater insight into when problems are occurring on the network and why.  With LANZ you will know when congestion happened, track the sources of congestion, and be able to export real-time events to external applications.  LANZ also shows the effect of packet buffering on an application as well as monitors and records packet drops during network congestion.  It is an invaluable tool which allows...
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DANZ Table of Contents

Tap Aggregation Introduction to Tap Aggregation Basic Use of Aggregation Groups Tab Aggregation Basic Settings Before You Start Filtering with Port ACLs Tap Aggregation VLAN List Filtering Tap Aggregation Traffic Steering Deep Packet Inspection Truncation on Tap and Tool Ports LLDP on Tap Ports Common Challenges with TapAgg TapAgg Glossary Advanced Mirroring Introduction to Port Mirroring Filtering with Port ACLs Latency Analyzer (LANZ) LANZ Architectures and Configuration LANZ Buffer Tuning Timestamping TimeStamping on the 7150 Timestamping Deep Dive and Frequent Questions Optics Tap Aggregation Optics Selection  

Data Analyzer (DANZ) Glossary

Access List (ACL) The switch configuration used for the purpose of filtering Layer 2, Layer 3, or Layer 4 traffic. See Filtering with Port ACLs Advanced Mirroring An Arista feature set which includes support for filtered, multi-destination mirroring, mirroring to EOS of data plane traffic, advanced load-sharing, and packet truncation.   Aggregation Group A configuration or grouping of Tap and Tool ports together where traffic from all Tap ports in a group will be replicated to all Tool ports in the same group.  A tool port can be a member of multiple aggregation groups whereas a tap port is allowed...
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How to collect interface statistics from bash

Watch interface counters, update interval 10 second (defined by the -n flag): [user@Arista ~]$watch -n 10 "FastCli -c 'show int e1 count rates'" Note: This command can also be run from the CLI: Arista#watch 10 show int e1 count rates Watch interface counters, update interval 10 second & highlight differences (defined by the -d flag): [user@Arista ~]$ bash watch -d -n 10 "FastCli -c 'sh int e1 count rates'" Note: This command can also be run from the CLI: Arista#watch 10 diff show int e1 count rates Collect the interface names and the corresponding IP addresses (for all interfaces) to a...
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Debugging EOS agents

EOS’s architecture is built around the notion of agents. While the CLI show commands offer some great insights into the operational status of the switch, there is deeper level of detail that can be gathered from the agents by using a EOS debugging feature called agent tracing. Through this feature, which delivers live debug output to the CLI, EOS provides extensive troubleshooting information and enables users to debug complex control plane or protocol layer interactions. To configure agent tracing, first check the list of available agents. For example, in order to see the list of all agent starting with ‘A’, use: Arista#show trace...
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How to store and view previous contents of ‘show tech-support’

Introduction Starting with EOS 4.8.1, Arista introduced a unique feature called CLI Scheduler. Besides helping with troubleshooting and debugging Arista switches, this feature is used in order to automatically save the last 100 outputs of show tech-support (taken every hour). Please see an Arista EOS Manual for further details on the CLI Scheduler. Scheduling a show tech-support command The schedule command facilitates the periodic execution of a specified CLI command. Command parameters can be used in order to configure: the interval between consecutive executions of the command the maximum number of log files to be saved Starting with 4.8.1, by default, the...
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SSH login without password

This article describes how you can configure your switch with a pre-shared SSH key from a host. 1. Create the user account on the switch   Arista(config)#username <user> privilege 15 secret <secret password> 2. Generate SSH key files on the SSH client host. If you already have the SSH key files, skip to step 3. <host>$ssh-keygen -t dsa -f testkey Generating public/private dsa key pair. Enter passphrase (empty for no passphrase): Enter same passphrase again: Your identification has been saved in testkey. Your public key has been saved in testkey.pub. The key fingerprint is: 38:dd:3a:68:ea:36:f1:9b:fa:69:ba:43:38:2f:98:f0 fred@HOST1.yourdomain.local The key's randomart image...
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