Control WRED threshold for non-ECT packets

This feature is an extension to the Explicit Congestion Notification (ECN) functionality for non-ECN-Capable Transport (non-ECT). It allows the user to configure Weighted Random Early Detection (WRED) thresholds for dropping non-ECT packets, which enables non-ECT packets to participate in WRED congestion avoidance independent of the ECT packets. Platform compatibility DSC-7050X DCS-7250X DCS-7300X Configuration The non-ECT thresholds are configured at an interface’s tx-queue level. The drop profile is defined by minimum-threshold, maximum-threshold, and drop-probability. The units for thresholds can be given in segments, bytes, kilobytes or megabytes. Please note that global config level qos random-detect ecn allow non-ect configuration is needed to allow (and not...
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Best Practise setup for NAS, iSCSI storage

Hi   I have 3 x 2 unit  MLAG setup.  on 2 of my mlag’s I have some Equal Logic storage.   I was wondering if there was any best practise or white paper on whats the next setup for my arista switches (DCS-7050SX-64-F), DCB is the requirement from equallogic, but I believe I can setup some QOS ?   any pointers ref would be welcome Alex

QoS Policy on Outbound Packets

I cannot choose to put a service-policy with output of packets, only input. This is on both a physical and vlan interface. Is this a limitation with code or hardware? There is only “input” available on the command “service-policy type qos input <name>”. I am running version 4.15.5M on TridentII chips (DCS-7050SX-64-F). ThanksTim

Shared ACL based QoS on SVIs

ACL based QoS programmed on SVIs can share hardware resources starting from EOS-4.17.0F. This results in a more efficient utilization of the system resources and is particularly useful for environments with a few, potentially large, QoS policy-maps applied to multiple SVIs. For more information on ACL based QoS support on SVIs, refer to ACL based Qos on SVIs. Platform compatibility DCS-7010 DCS-7050X DCS-7250X DCS-7300X Configuration By default, the sharing of ACLs is disabled. The CLI command used to enable it is: 7050(config)#hardware access-list qos resource sharing vlan in The CLI command to disable it is: 7050(config)#no hardware access-list qos resource sharing vlan in Status Show Commands...
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Show command for fabric interfaces

The show command ‘show qos interface fabric’ was introduced for DCS-7250QX and DCS-7300X series starting EOS-4.15.2F release, which just displayed the Qos profile applied on the fabric interface. This command has now been modified to display detailed information about configured/operational values of interface Qos configurations, as is shown by the command – ‘show qos interfaces <intfName>’ for front panel ports. Variants of the command have also been added to display information of fabric ports across all chips and to display ECN thresholds for ECN configuration on the ports. Platform compatibility DCS-7250X DCS-7300X Configuration All configurations on the fabric port is through...
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QoS Profiles

QoS profiles are a collection of interface level QoS configuration commands, that are used as an alternate means of input to the traditional CLI. They help in reducing clutter in the running configuration. A possible use-case would be when there are common QoS configuration statements that need to be applied or modified on multiple interfaces. Introduced first for the DCS-7250QX and DCS-7300X series with the EOS-4.15.2F release, they have been improved upon in this release. Previously, they were applicable only on the fabric interface and supported priority flow control, tx-queue ECN, WRED and guaranteedBandwidth configurations. Now they are also applicable...
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