• Tag : Bash


VRF interaction using EOS and Bash

Overview: Virtual Routing and Forwarding, or VRF, is a construct within Arista’s Extensible Operating System, or EOS, that provides a network administrator with the ability to delineate network communications at the Network layer of the OSI 7-layer model. When defining the attributes of a VRF, you can place your EOS CLI session into the context of the desired VRF. The technique of entering a VRF context has particular utility when you need to work more exclusively with a specific VRF. Doing so can help avoid redundant target VRF references with each pertaining command. Placing yourself into a VRF context can...
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Monitoring some agent’s memory utilisation

  Monitoring some agent’s memory utilisation   This article develops further https://eos.arista.com/introduction-to-managing-eos-devices-memory-utilisation/ authored by Colin MacGiollaEain to bring the context to a specific agent’s memory utilisation and how to remediate.   1) Introduction Monitoring the memory usage of specific EOS processes maybe useful to detect which features consume the control-plane resources, as a first step to clarify whether it is a normal behaviour or not. In abnormal circumstances the overall system may be running low on memory, in which case some culprit agent may be restarted, or some other agent may suffer a restart too (collateral damage) by the process scheduler. Examples...
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Bash ifconfig not showing intefaces assigned to VRFs

Hello All! I am attempting to perform a tcpdump on an SVI assigned to a non-default VRF.  When I drop to the Arista Bash CLI and run the ‘ifconfig’ command, I do not see the SVI listed.  I do not see any interface or SVI assigned to a non-default VRF in the list. Does anyone know how I would view ifconfig details on interfaces assigned to VRFs? My gear is:Arista DCS-7050SX-128-FSoftware image version: 4.17.1F

Why Bash and Cli responce different ?

Hi all, I have 3 questions. 1. When I use bash command “ifconfig” from Arista SW. It showing “CPU” , why ifconfig show CPU ? When I use ifconfig command on Linux server, it doesn’t show CPU. Why “CPU” showing bash command “ifconfig” ? 2. Why different MAC address show , Cli and bash ? 3. Bash ifconfig show same MAC address for all interface , why ? Thank you,Toshi.

issue using event-handler with bash command

Hi, I run vEOS 4.13.7M in VirtualBox. Inspired by the logGrab bash script provided here on EOS Central I wrote this tiny little script #!/bin/bash FILENAME=startup-config_$HOSTNAME_$(date +%Y-%m-%d.%H%M%S) cd /mnt/flash cp startup-config $FILENAME Invoked from CLI it works like a charm, producing lots of config files to fill my flash: Leaf1#bash /mnt/flash/archive_startup_configs.sh Leaf1#dir Directory of flash:/ -rwx         154           Feb 19 16:52  archive_startup_configs.sh -rwx          20           Jun 16  2014  boot-config drwx        4096           Aug 22  2014  debug drwx        4096           Feb 19 07:44  persist drwx        4096           Aug 22  2014  schedule -rwx        1062           Feb 19 16:53  startup-config -rwx        1062           Feb 19 16:26  startup-config_2015-02-19.162615 -rwx        1062           Feb...
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Introduction to Managing EOS Devices – EOS Tips for Power Users

Note: This article is part of the Introduction to Managing EOS Devices series: https://eos.arista.com/introduction-to-managing-eos-devices/      Annex B)  EOS Tips for Power Users B.1) CLI – Show Commands Redirections   EOS CLI supports the following “show” command redirections, by “|” (pipe): LINE      Filter command by common Linux tools such as grep/awk/sed/wc append    Append redirected output to URL begin     Begin with the line that matches exclude   Exclude lines that match include   Include lines that match no-more   Disable pagination for this command nz        Include only non-zero counters ← Hides line with all 0 numbers redirect  Redirect output to URL section   Include sections that match...
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Understanding CPU Utilization

Introduction This article explains the different values from the CPU utilization output, down to the per-thread CPU usage on an Arista EOS. To this aim, we will cover the topics in different sections, as follows: How to view the CPU usage Understanding CPU Usage – Row 1 Understanding CPU Usage – Row 2 Understanding CPU Usage – Row 3 Understanding CPU Usage – Row 4 Understanding CPU Usage – Row 5 How to view CPU usage on a multi core switch? Understanding CPU Processes     1) How to view the CPU usage To view the CPU usage, use the...
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Using tcpdump for Troubleshooting

What is tcpdump? tcpdump is a command line packet sniffer (built into Linux) that is used to assist in troubleshooting network problems. Any traffic coming to or from the control plane of the Arista is visible when running the tcpdump utility on the Arista.  This does not include data plane traffic transiting the Arista switch.  For capturing data plane traffic, Arista supports monitoring/SPAN ports which copies hardware-forwarded traffic to a sniffer or to other suitable capture device for analysis.  You can also mirror to the CPU depending on platform and EOS image (https://eos.arista.com/eos-4-24-0f/mirroring-to-cpu-on-7050-7060-7260-7368-7300-and-720xp-series/).   How do I use tcpdump to...
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Restarting EOS agents

Objective This article shows an experiment which demonstrates what happens when an EOS agent is killed (either voluntarily, or as a result of a failure). Preparation (optional) In the frame of this article, and for testing purpose only, we take few preparation steps that are not absolutely necessary in a production environment: 1) Clear the logs to improve visibility (less noise in the logs) Arista#clear logging 2) Configure high resolution logging timestamps Arista (config)#logging format timestamp high-resolution Killing an agent 1) Access the bash shell Arista#bash 2) Select a process and find its PID (Process ID) [admin@Arista ~]$ ps –ef |...
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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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