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by jimmar 1088 days ago
> old Cisco architecture via Core/Access/Distribution, where larger DC networks have converged onto spine/spline setups

Please correct me if I'm wrong, but I see the "old" core/access/distribution layers still relevant. The datacenter spine/spline setup applies to networking between server racks in the data center.

> 802.1q VLAN tags: access versus trunk

Again, are you saying that these are outdated? I'm not a practicing network engineer, but I know several network engineers and they've told me that understanding 802.1q VLAN tags to segment network traffic has been helpful.
2 comments
kazen44 1088 days ago
> Please correct me if I'm wrong, but I see the "old" core/access/distribution layers still relevant. The datacenter spine/spline setup applies to networking between server racks in the data center.

this is correct. The place where spine-leaf really shines is when used in combination with evpn-vxlan. You can then encapsulate every tenant network inside a VXLAN domain and route those between your leafs switches through your spine layer.

This is basically a clos fabric which is non-blocking, and is very easy to expand horizontally. It also gives you nice features like ARP suppression[0]. These features are important in a DC fabric because ARP flooding is traffic which is not revenue generating, and should be minimized as much as possible.

For normal Enterprise/Office network, running an evpn-vxlan fabric is usually far to complex for the benefits involved.

[0] https://satishdotpatel.github.io/how-does-arp-suppression-wo...

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darkr 1088 days ago
> 802.1q VLAN tags: access versus trunk

I think the parent was saying that these are Cisco specific terms; more generic terms would be "untagged" + "tagged".

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ajsnigrutin 1088 days ago
Trunk and access ports are like kleenex and bandaids. Yes, technically cisco terminology, but used everywhere.
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iso1631 1088 days ago
Absolutely, here's a config from one of my aristas(with bits snipped)

   interface Ethernet1
      switchport trunk native vlan 899
      switchport trunk allowed vlan 801
      switchport mode trunk
   interface Ethernet13
      switchport access vlan 311
And on a Juniper

   set interfaces xe-0/2/1 unit 0 family ethernet-switching interface-mode trunk
   set interfaces xe-0/2/1 unit 0 family ethernet-switching vlan members Mgmt_B
   set interfaces xe-0/2/1 unit 0 family ethernet-switching vlan members Audio_2
   ....
   set interfaces ge-0/0/19 unit 0 family ethernet-switching interface-mode access
   set interfaces ge-0/0/19 unit 0 family ethernet-switching vlan members Audio_2
When Cisco, Arista, Juniper all use access vs trunk it's hardly a vendor specific term
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