• Tag : EOS


Must I use all the same version of EOS for switches and CVX?

Hi, there. I’m using 5 Arista switches with EOS(4.24.4M) and CVX (4.24.0F). I’m trying to upgrade one of switches to Is it OK to use one different version of EOS? (maybe any faults… between 4.24 CVX and 4.26 EOS??) Have any ideas? Thank you !

NAT support for containerized EOS

I use cEOS-lab to test switch configurations before deploying them on the actual hardware. From other forum posts I understand that cEOS-lab does not support NAT. Is this correct? Is there a containerized version which supports NAT or do only the VM based EOS solutions (non-lab) support NAT. It would be nice if this were shown here: https://www.arista.com/en/support/product-documentation/supported-features Thanks!

EOS default route preferences

Description The document captures the default preference value (between 0 and 255) for routes from various supported protocols. Note that some the preference value may be overridden by configuration in the respective source protocols. Route Protocol/Source Default Route Preference Connected 0 Static 1 VxLAN Control Service 1 DHCP IPv6 Prefix Delegation 15 Kernel 40 OSPFv2 110 OSPFv3 110 IS-IS 115 RIP 120 iBGP 200 eBGP 200 BGP Aggregate 200 Dynamic Policy 240 Routes leaked across VRFs retain the route preference from the source VRF. Show commands The show ip route and the show ipv6 route commands show the route preference...
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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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A simple GNU sed example on EOS

Hopefully by now you are aware that Arista EOS (Extensible Operating System), which is the operating system that runs on Arista switches, is based on Linux. From the CLI you can drop to the Bash shell by just typing bash. Given that EOS is based on Linux you already have access to many of the helpful utilities seen in many Linux distributions. Let’s pretend that you have a configuration file that was copied over from another very similar configuration and that the only thing that needs to change is every occurrence of IP addresses that look like 10.0.x.y. This is...
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A Simple Quality of Service Design Example

While there is plenty of documentation available discussing the individual mechanics of Quality of Service, such as Class of Service (CoS) or Differentiated Services Code Point (DSCP) markings and what they mean, there is not as much documentation available bridging the gap from those basic building blocks to a working network QoS deployment. There are some understandable reasons for that lack of documentation, because the design and implementation of a QoS policy on a network is so closely coupled to the specific network’s business objectives and policies that it’s hard to develop much of a QoS policy and have it...
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Arista EOS – IPv6 RFC Compliance

Arista EOS Software is in compliance with the following IPv6 RFCs: RFC 8200 – Internet Protocol, Version 6 (IPv6) Specification RFC 4861 – Neighbor Discovery for IP version 6 (IPv6) RFC 4862 – IPv6 Stateless Address Autoconfiguration RFC 4443 – Internet Control Message Protocol (ICMPv6) for the Internet Protocol Version 6 (IPv6) Specification RFC 8504* – IPv6 Node Requirements RFC 1981 – Path MTU Discovery for IP version 6 RFC 2464 – Transmission of IPv6 Packets over Ethernet Networks RFC 2474 – Definition of the Differentiated Services Field (DS Field) in the IPv4 and IPv6 Headers (IPv4) RFC 4213 –...
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A Simple OSPF Configuration

At this point in your networking career you’ve mastered the L2 domain. I can recall several years ago when I was an embedded software engineer (programming NPUs – Network Processing Units for a networking startup) meeting a colleague that was a master of the L2 domain. This individual knew everything you wanted to know about L2, including non-Ethernet protocols. Then came the day when I was drawing a network diagram with L3 interfaces and diagramming the packet formats at the points of ingress and egress through each L3 hop. My L2 Grandmaster looked at me with a blank stare. I...
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clear platform trident counters

Hi Forum we currently troubleshoot input discards. we found the rich command show platform trident counters for our platform.(DCS-7050SX3-48YC8-F) I’ve tried to reset counter to have a blank situation. I’ve used: clear platform trident counters this cause reset of all interfaces in LAG on this switch. January 23rd 2020, 10:22:02.000 MODULE_RESET 6 Informational Switch Linecard0/0 restarting. Cause: Strata-FixedSystem crashed January 23rd 2020, 10:22:02.000 UNEXPECTED_RESTART 3 Error Unexpected restart of Strata agent Strata-FixedSystem occurred after my mistake i’ve checked the documentation about this clear command, but i didn’t found any reference. does someone has knowledge what the clear platform trident counters...
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Hybrid cloud connectivity with Arista’s Extensible Operating System (EOS) and Amazon Web Services (AWS)

Motivation The term Hybrid Cloud is not clearly defined but the most common definition is a scenario where a customer wants to combine resources in their own data centre (the private cloud) with resources in the public cloud. To allow these services to communicate, a connection between the two cloud environments needs to be established. Most cloud providers offer two options: An Internet Protocol Security (IPsec)-based Virtual Private Network (VPN) connection using the Internet as a transport media and a private link using dedicated lines or equivalent technology. In this article, we cover the VPN based approach using EOS-based services...
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How do I know which version of code I should run?

Newish to Arista. I have a pair of DCS-7280SR-48C6-M-F that I am getting ready to deploy. They’re currently running, but that was loaded months ago in the lab. How do I know which version of code I should be running? Does Arista have a software selector tool or matrix to help guide customers to the most appropriate release? Thanks. Mike

DCS-7124 EOS Versions?

Hi all; Very new to Arista; I have a dcs-7124sx and was wondering what the latest and greatest version of EOS I can safely upgrade this to? does anyone know if there is a limit? Docs say End of Life EOS 4.1.3; but i just performed full recover on this switch and its booting 4.6.2? Thus my question regarding the EOS version I can install. Thank You for any help…

Network CI/CD Part 1 – Building network topologies with Docker and cEOS-lab

Introduction As the networking industry continues riding the DevOps wave and network engineers become more comfortable using automation tools like Ansible and Salt, network still remains the most brittle piece of IT infrastructure. Partially this can be justified by the fact that network underpins all other areas of IT infrastructure stack – compute, storage and virtualisation. However we, as network engineers, have done very little to improve our confidence in networks and until now some of the biggest outages were caused by trivial network configuration mistakes. When software industry was facing similar challenges, the response was to create Continuous Integration (CI) pipelines –...
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vEOS-Lab on Hyper-V

Introduction There are multiple ways to setup a vEOS-Lab environment if you have a linux system or on hypervisors such as VMware ESXi, vCenter, VM Workstation, VM Fusion, Virtualbox, etc using the vmdk provided in the Software downloads page. But if you have a Windows machine or a Windows server, the vmdk will not be useful. So here are the steps on how you can convert the vmdk to a  vhdx and create a vEOS VM on Hyper-V. Pre-requisites 1. Hyper-V Manager and Hyper-V 2. vEOS-Lab vmdk 3. Aboot ISO  Instructions Steps 1. Download the vEOS vmdk for the EOS version...
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vEOS Router Architecture

One of the benefits of the vEOS router is that it runs the same code as normal EOS, but in a virtual machine instead of on a hardware switch. Thanks to the EOS’s modular architecture, supporting a virtual machine instance is as simple as adding different agents to the system to accommodate the virtual network drivers. In this post, I describe how the different virtual networking options work with vEOS both on a server and in the cloud. Then I will explore some of the differences between vEOS router, vEOS-lab, and EOS on a hardware switch. For more information on...
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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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