• Tag : LAG


New CLI commands to disable/enable IP protocol field in LAG hashing

Description A Link Aggregation Group (LAG) is used to aggregate/gather together multiple physical links into a single logical link. In addition to offering increased availability, LAGs also offer increased bandwidth proportional to the number of total physical interfaces bundled into a LAG. To utilize the maximum possible bandwidth that can be achieved, the traffic across a LAG needs to be effectively balanced across all the member interfaces. This is done by using a LAG hashing algorithm that uses a subset of values from packet or framer headers to compute a hash value. This hash value determines the active member link...
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Port-channel Minimum Speed Review and Retry Mechanism

Description Starting from 4.26.10F release, for LACP and static port-channels, EOS will support minimum speed configuration, along with review timer and retry timer. Minimum speed is the total speed of all the interfaces configured in the port-channel which is needed to bring the port-channel link up. If both min-links and minimum speed are configured for a port-channel, minimum speed takes precedence over min-links. Min-links feature is only applicable on the port-channel with all member interfaces having the same speed. Minimum speed feature is applicable for both: port-channel with all member interfaces having same speed; port-channel with member interfaces having different/mixed...
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Disable ingress interface from LAG hashing

Description In older EOS releases the ingress interface was always included in LAG hash calculations input together with other currently configured fields, for instance source/destination MAC addresses, source/destination IP addresses and or L4 ports, etc. A new CLI was added to control the inclusion of the ingress interface to the LAG hash.  Having an ingress interface as one of the inputs to LAG hash calculation ensures that the same flows of packets (identified by a unique set of selected packet fields) will be transmitted out of different members of a LAG. There may be a need to disable this behavior,...
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Adding MLAG to existing configuration impact

Hello, I’m a bit new to Arista but I have 1 in my environment I work with.  For a long time we had a single Arista switch running a set of hosts.  Recently we procured a second one to add in HA with MLAGs.  I am going through the planning to add the new switch and hoping to avoid any outages but from what I tell theres really no way around an outage. So currently we have a compute system connected in a LAG on port-channel 1 via 2 of its 40gb ports. We have LAG on port-channel 2 to...
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Maximum port channel ID increase

Description Previously, the maximum valid port channel ID was equal to the maximum number of port channels configurable on the system, 2000, and this feature increases the maximum ID to 999,999 while maintaining the same limit of 2000 port channels on the system. Platform compatibility DCS-7010 DCS-7020 DCS-7050 DCS-7060 DCS-7250 DCS-7260 DCS-7280 DCS-7500 DCS-7516 DCS-7800 DCS-7808 Configuration This feature does not involve any specific configuration procedure, but it does include visible changes to port channel configuration commands. In the following examples, suppose port channels 1-2000 have already been configured, so creating Port-Channel2001 would exceed the config limit. switch(config)#interface create port-channel...
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40G port-channel/LAG flatlining around 10 Gbps

We have two Arista 7504’s, each with a downstream-facing LAG into the same Cisco 7600-series router. Both were flat-lining around 10 Gbps, so thinking that perhaps it was the downstream router, we spread the traffic around by adding a fourth 10G to each LAG. Yet we’re flat-lining around the same value — adding that fourth LAG member made no perceptible difference. There are no deferred or output discards on the port-channel or individual ports, so my remaining thought is that there is some kind of rate-limiting going on in the Aristas that we can’t see. Is there anything that needs...
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Arista 7280QR-C36 Load Balancing Optimization for Dual Homed Systems and Networks

Arista 7280QR-C36  The Arista DCS-7280QR-C36 switch is a purpose built flexible fixed configuration 1RU system capable of supporting a wide range of interface choices. Its designed for the highest performance environments such as IP Storage, Content Delivery Networks, Data Center Interconnect and IP Peering. The 7280QR-C36 is optimized for environments with dual connected nodes such as storage and for spine applications with dual homed leaf switches. This technical application note describes the internal optimized load-balancing mechanism used within the switch and how network architects can best deploy this system to maximize overall system performance. The internal architecture of the DCS-7280QR-C36...
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Global LAG Hashing Profiles

Users can now define a global LAG hashing profile. The global LAG hashing profile will be applied to all linecards which do not have a specific LAG hashing profile assigned to them. Platform compatibility This feature is available starting in EOS 4.17.0F on 7500E and 7500R systems. Configuration The user selects a LAG hashing profile to be designated global 7500(config)#port-channel load-balance sand profile ? WORD Name of the load-balance profile 7500(config)#port-channel load-balance sand profile myGlobalProfile The ‘default’ profile is a special profile which cannot be deleted and will be set to global if no other profile is selected to be...
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Hi, I have a arista switch whose interface is connected to the cisco dut interface. When I am making the cisco dut interface ‘no shutdown’ and checking it I am getting the interface status as ‘Suspended’. All the configuration parameters are same. What are the reasons under which the interface can go into ‘Suspended’ state apart from the configuration parameter.

Palo Alto / Arista LAG HOWTO

This is a quick guide on configuring a LAG (802.1ad LACP) between a PAN-5060 firewall and an Arista switch. * *Pre-requisite: PANOS 6.1 or above PAN Cli config:  set network interface aggregate-ethernet ae1 layer2 lacp enable yes set network interface ethernet ethernet1/3 aggregate-group ae1 set network interface ethernet ethernet1/4 aggregate-group ae1 set network interface aggregate-ethernet ae1 layer2 units ae1.100 tag 100 set address ip-netmask set network profiles interface-management-profile Trust https yes set network profiles interface-management-profile Trust ssh yes set network profiles interface-management-profile Trust snmp yes set network profiles interface-management-profile Trust ping yes set network interface vlan units vlan.100...
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Configure LACP with 2 ports of different switches

Hi, I’m having setup as explained in the below link. https://eos.arista.com/wp-content/uploads/2014/03/esxlacp5.png I want to create LACP LAG using 2 ports connected to different switch as mentioned in diagram. I’m not able to find the way to configure using 2 switches, please help me to do this.

Configuring LACP Fallback Individual Ports on Arista Switches

LACP Fallback Individual Ports Feature Overview LACP Fallback Individual Ports is a feature introduced in EOS 4.13.0 that allows all ports in a port- channel to fallback to individual switch ports when negotiation fails The feature is applied to the port-channel interface and consists of two configuration elements which will be described in the following sections Setting the port-channel to individual fallback Setting the fallback timeout   Feature Operation LACP Fallback Individual Ports use cases This feature is useful for servers with multiple NICs where it is difficult to predict which NIC the server might use for PXE boot. Summary of...
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MLAG – basic configuration

MLAG overview LAG or link aggregation is a way of bonding multiple physical links into a combined logical link. MLAG or multi-chassis link aggregation extends this capability allowing a downstream switch or host to connect to two switches configured as an MLAG domain. This provides redundancy by giving the downstream switch or host two uplink paths as well as full bandwidth utilization since the MLAG domain appears to be a single switch to Spanning Tree (STP). Because the MLAG domain appears to STP as a single switch there are no blocked ports. Configuration The following will provide instructions on how...
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How to configure Link Aggregation Groups in EOS

This article describes the configuration of Link Aggregation Groups (LAGs) between two Arista 7050T-64 switches. The configuration examples are not specific to the switch model and this guide should apply to configuring LAGs on all Arista hardware. Static Link Aggregation Configuration of 7050-01 7050-01(config-if-Et17-20)#channel-group 200 mode on Once the above sequence is entered, Ethernet interfaces 17 through 20 are bound in a LAG as port-channel 200: 7050-01#show int po200 Port-Channel200 is down, line protocol is lowerlayerdown (notconnect) Hardware is Port-Channel, address is 001c.731c.46f9 Ethernet MTU 9214 bytes Full-duplex, Unconfigured Active members in this channel: 0 Fallback mode is: off Fallback...
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