Dell Active Fabric Manager, Руководство по развертыванию

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Type 4: Small Distributed Core Fabric
Use the Type 4: Small Distributed Core design when:
• You require a fabric interlink bandwidth between the spines and leaves of 10 GbE.
• The current and future planned uplinks and downlinks on the leaves for your core is less than or equal to 960
ports.
• The maximum port count for a Type 4: Small Distributed Core fabric with an OS ratio of 3:1 is 768. For an OS ratio
of 5:1, the maximum port count is 896.
• The leaves act as a switch or ToR-leaf switch. Within the ToR, the downlink protocol can be either VLAN or
VLAN and LAG.
With a Type 4: Small Distributed Core fabric design, the S4810 spines connect to the S4810 leaves at a fixed 10 GbE. The
maximum number of spines is 4 and the maximum number of leaves is 16, as show in the following figure.
Figure 7. Type 4: Small Distributed Core Fabric Design
Each S4810 leaf for the Type 4: Small Distributed Core design has the following:
• Sixteen 10 Gigabit of fabric interlink port capacity to the spine
• Forty–eight 10 Gig Ethernet downlinks
• Sixty 10 Gig Ethernet ports for servers per node and WAN connectivity
VLT
Virtual link trunking (VLT) allows physical links between two chassis to appear as a single virtual link to the network core
or other switches such as Edge, Access or Top of Rack (ToR). VLT reduces the role of Spanning Tree protocols by
allowing LAG terminations on two separate distribution or core switches, and by supporting a loop free topology. (A
Spanning Tree protocol is still needed to prevent the initial loop that may occur prior to VLT being established. After VLT
is established, RSTP may be used to prevent loops from forming with new links that are incorrectly connected and
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