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In a leaf-spine network switch architecture, the access layer of the network is referred to as the leaf layer. The PowerScale nodes connect to leaf switches at this layer. At the next level, the aggregation and core network layers are condensed into a single spine layer. Every leaf switch connects to every spine switch to ensure that all leaf switches are no more than one hop away from one another. Also, leaf-to-spine switch connections must be evenly distributed, meaning there must be the same number of connections to each spine switch from each leaf switch. This practice minimizes latency and the likelihood of bottlenecks in the back-end network. A leaf spine network architecture is highly scalable and redundant.
Leaf spine network deployments can have a minimum of two leaf switches and one spine switch. For small to medium clusters in a single rack, this back-end network consists of two redundant top-of-rack (ToR) switches rather than implementing a leaf-spine deployment. Only the Dell S5232-ON, Z9100-ON, and Z9264-ON Ethernet switches are supported in the leaf-spine architecture.
Dell Switch | Dell SKU | Back-end ports | Port type | Rack units | 100 GbE and 40 GbE nodes | Mixed environment (10, 25, 40, and 100 GbE) |
S5232-ON | 210-BCVB | 32 | All 100 GbE | 1 | 32 or less | Support breakout cables of 4 x 10 GbE or 4 x 25 GbE. Total of 124 10 GbE or 25 GbE nodes as ToR back-end switch. Port 32 cannot be used for a breakout cable. |
Z9100-ON | 210-AWOV /210-AWOU | 32 | All 100 GbE | 1 | 32 or less | Support breakout cables of 4 x 10 GbE or 4 x 25 GbE. Total of 128 10 GbE or 25 GbE nodes as ToR back-end switch. |
Z9264-ON | 210-AWOW | 64 | All 100 GbE | 2 | 64 or less | Support breakout cables of 4 x 10 GbE or 4 x 25 GbE. Total of 128 10 GbE or 25 GbE nodes as ToR back-end switch. |
Note: The use of breakout cables on the Z9264-ON switch disables the adjacent port; breakout cables are supported on odd numbered ports only.
Note: The Dell supported switches are shipped with a fixed configuration and additional customer configuration is not supported. Any switch updates (such as DNOS and firmware) need to be performed by a Dell qualified resource.
While the S5232-ON, Z9100-ON, and Z9264-ON support many features, not all capabilities of the switch are exposed or required when the switch functions as a PowerScale back-end switch (see Table 2).
Component | Description | Connection considerations |
Network Spine Switch | Dell S5232-ON 32-port switch | Back-end network with 100 GbE (uplink) connects to the leaf switch. |
Network Leaf Switch | Dell S5232-ON 32-port switch | Downlink from the leaf switch to the nodes. Supported connection type 100 GbE, 40 GbE, 25 GbE, and 10 GbE back-end nodes. 25GbE and 10GbE node connections are supported by breakout cable only. |
Dell PowerScale All-Flash nodes | F910, F900, F710, F600 F210, F10
| F910, F900, F710 and F600 nodes support a 40 GbE or 100 GbE connection to the leaf using the same NIC. F210 and F200 nodes support 40 GbE or 100 GbE connection to the leaf using the same NIC. |
Dell PowerScale Hybrid and Archive nodes | H700, H7000, A300, and A3000 | Supports 40 GbE or 100 GbE connection to the leaf using the same NIC. |
Dell Isilon Performance and Hybrid nodes (Gen6) | F810, F800, H600, H500, and H5600 | Performance nodes support a 40 GbE connection to the leaf switch. |
Dell Isilon Archive and Hybrid Nodes (Gen6) | A200, A2000, and H400 | Archive nodes support a 10GbE connection to the leaf switch using a breakout cable. Use a breakout cable to connect up to four nodes to a single leaf port. This cable connects a leaf switch 40 GbE port to four 10 GbE nodes or a leaf switch 100 GbE port to four 10 GbE nodes. |
Note: OneFS 9.0 requires the switch operating system version for the Z9100 and Z9264 switches to be 10.5.0.6C3. The Dell Networking OS (DNOS) version 10.5.0.6C3 is also supported in OneFS version 8.2.2. 144-node Leaf/Spine (L/S) clusters can still work with older versions of DNOS version 10.4.x. DNOS version 10.5.0.6C3 requires manual designation of leaf and spine switches through the command line from the switches. DNOS version 10.5.2.9 has been qualified for all supported Dell Ethernet switches for PowerScale leaf-spine configurations.
The S5232-ON switch requires the switch operating version to be 10.5.2.9. When installing a S5232 switch into an existing leaf-spine cluster that has either a Z9100 or Z9264 (or both), those switches will need to be upgraded to 10.5.2.9.
For detailed instructions for upgrading to the Dell Networking operating system, see the Leaf-Spine Cluster Installation Guide.