Analyzing Packet Header Timestamps in Wireshark

Arista Packet Header Timestamps EOS 4.18.1F added header time stamping of all packets received on any tap interface in Tap Aggregation mode on the 7500/7280E and 7500/7280R. Full details on the implementation can be found in the feature’s TOI: https://eos.arista.com/eos-4-18-1f/tap-aggregation-ingress-header-time-stamping/ Since the timestamp is a new ethernet header, Wireshark doesn’t yet have a built in dissector for the protocol. We can write a dissector in Lua to do this for us. Header Format First we need to understand the new header format. The timestamp header is a new Ethernet/L2 header consisting of the Arista EtherType (0xD28B), a two-byte protocol subtype of 0x1, a...
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Automate switch port configuration with EosSdk

Switch migrations are part of life in any datacenter, whether to add capacity with a larger system or new capabilities with a later product generation. There are two parts to this task – loading a configuration and the “rack and stack” of physical installation and cabling. Configuring the new new leaf switch is greatly simplified by tools such as ZTPServer. You can even use LLDP to verify that you’ve cabled the switch to its neighbors correctly. However, when it comes to plugging in servers, you still depend on a very manual process. This can be straight forward when you’ve a single VLAN...
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