Scaling - Dell PowerEdge R730xd Deployment Manual

10GbE 38
10GbE 38
10GbE 38
4.3

Scaling

An example of scaling this solution in a two-tier leaf-spine is a configuration of up to 16 racks. The Dell/EMC
Z9100-ON has thirty-two 40/100GbE interfaces that would support 16 leaf pairs using VLT. This provides one
rack that contains WAN-edge connectivity and 15 racks for servers and storage nodes. Each rack of the
compute/storage rack holding a combination of up to 19 PowerEdge R730's or Isilon X210's.
This particular example, each R730 has four 10GbE uplinks, and each Isilon node has four 10GbE uplinks
with 19 servers/nodes per rack. Additionally, the example architecture has four spine switches to minimize
oversubscription.
Connections
Speed of
Ports
Total
theoretical
available
bandwidth
This example provides for an oversubscription rate of 2.375:1 using 40GbE spine connectivity.
Scaling beyond 16 racks would require a three-tier leaf-spine network. The proof-of-concept scaling that
Figure 11 shows allows four 16-rack pods connected using an additional spine layer to scale in excess of
1,000 nodes with the same oversubscription ratio. This scenario requires reducing the number of racks
available per pod to accommodate the uplinks required to connect to the super spine layer.
It is important to understand the port-density of switches used and their feature sets' impact on the number of
available ports. This directly influences the number of switches necessary for proper scaling.
13 Dell EMC Networking with Isilon Front-End Deployment and Best Practices Guide | version 1.0
380GbE
380GbE
380GbE
Connections for 16 racks with 4 spine switches
Server/Storage
interfaces
4
10 GbE
4 x 10 =
40GbE
2 100GbE
3 100GbE
4 100GbE
Server Leaf connections to spine
connections to switches per rack
leaf switches
19 x 4 = 76 4 per leaf switch, 2 leaf
switches per rack = 8 links
10 GbE 40 GbE
76 x10 = 8 * 40GbE per rack =
760GbE 320GbE
80GbE 380/200
120GbE 380/300
160GbE 380/400
Total connections for leaf
switches to four spine
switches
16 racks * 8 = 128
40 GbE
16 * 320GbE = 5120GbE
1.900 : 1
1.267 : 1
0.950 : 1