• Author : Anais Taing

 
 

TAP Aggregation – FCS handling 

Description In TAP Aggregation mode, when receiving a packet whose Frame Check Sequence (FCS) is corrupted, the default behavior on the 7280E/R/R2 and 7500E/R/R2 series is to replace the bad FCS with the correct value and forward it. Configuration options are available to control the FCS behaviour, such as to discard errors, or append a new FCS. Platform compatibility DCS-7280E/R/R2 series DCS-7500E/R/R2 series Configuration A global TAP Aggregation command is used to configure the behavior regarding the FCS behavior. To discard the packets with a corrupted FCS: Arista(config-tap-agg)#mac fcs-error discard To revert to the default behavior, i.e. to replace the...
Continue reading →

Tap Aggregation Timestamp Keyframes

Description The Tap Aggregation timestamping on the 7500 series supports both timestamping packets in TAI (International Atomic Time) since EOS-4.18.1F, and UTC (Coordinated Universal Time) since EOS-4.22.0F (see Packet Time Stamping on the 7500R/7280R/7500E/7280E). When using the TAI format for timestamping, keyframes can be used to correlate TAI time from the timestamping header to corresponding UTC time.   A keyframe contains ASIC time in TAI format and the equivalent UTC time and it also holds PTP (Precision Time Protocol) information from the switch, like the last synchronization time.   For the Arista switch to be aware of the number of...
Continue reading →

TAP Aggregation – FCS error handling

In TAP Aggregation mode, when receiving a packet whose Frame Check Sequence (FCS) is corrupted, the default behavior on the 7280E/R/R2 and 7500E/R/R2 series is to replace the bad FCS with the correct value and forward it. Configuration options are available to control the FCS error behaviour, such as to discard errors. Platform compatibility DCS-7280E/R/R2 series DCS-7500E/R/R2 series Configuration A global TAP Aggregation command is used to configure the behavior regarding the FCS errors. To discard the packets with a corrupted FCS: Arista(config-tap-agg)#mac fcs-error discard To revert to the default behavior, i.e. to replace the corrupted FCS with the correct...
Continue reading →

Follow

Get every new post on this blog delivered to your Inbox.

Join other followers: