Planning for I/O connections

Plan to install the appropriate adapters for your FlashSystem control enclosure so that it is compatible with your networking topology and provides the appropriate connection capability.

The control enclosure contains two node canisters. Each node canister has three PCIe interface slots, where two are used for host adapter cards. In addition, each node canister contains four Onboard Ethernet ports.

Important: Both node canisters in a control enclosure (I/O group) must be configured with the same adapters.
Note: The node canister in the upper slot (slot 1) of a control enclosure is inverted, so the adapter slots and port numbers are numbered from right to left. The adapters and ports of the node canister in the lower slot (slot 2) are numbered left to right.
Table 1 provides examples of the connection types and the alternative connection methods if alternative connection methods are available.
Table 1. Communications types
Functionality Network speeds supported On-board or Adapter Host I/O System to system Storage virtualization
Fibre Channel SAN (SCSI) 32 Gb, 16 Gb Adapter: 4-port yes yes yes
Fibre Channel SAN (FC-NVMe) 32 Gb, 16 Gb Adapter: 4-port yes no no
Ethernet (iSCSI) 25 Gb Adapter: 2-port yes yes yes
10 Gb On-board: 4-port yes yes no
Ethernet (NVMe/TCP and NVMe/RDMA) 25 Gb Adapter: 2-port yes yes no
Note: 2 port adapter with port speed 25 Gb or 10 Gb depends on transceiver installation. For more information on the adapter, see Cable reference.

Connecting two control enclosures directly with Fibre Channel cables

Two control enclosures can be directly connected to form a partnership (for policy-based high availability, migration or replication).

It is best for reliability, availability, and serviceability for control enclosures to communicate with each other through network switches. However, they can be directly connected with Fibre Channel (FC) cables, if needed.

Each node canister must have at least two paths to each node canister in the other control enclosure. This means that at least 8 Fibre Channel cables are needed and at least four Fibre Channel ports on each node canister will be used. Table 2 shows an example of Fibre Channel connections between the enclosures.
Table 2. Cabling to direct-connect two control enclosures
  Control enclosure 1   Control enclosure 2  
FC Cable Node Canister FC Port Node Canister FC Port
1 1 1 1 1
2 1 2 2 1
3 1 3 1 2
4 1 4 2 2
5 2 1 1 3
6 2 2 2 3
7 2 3 1 4
8 2 4 2 4