Node configuration details

Apply these configuration details to nodes to ensure that you have a valid configuration.

Host bus adapters and node canisters

Each node canister in a FlashSystem 5010 or FlashSystem 5015 control enclosure has two onboard ports for 1 Gbps Ethernet (port 2 on each node canister is also used as a technician port) and one 12 Gbps SAS port for 1 chain of expansion enclosures. The node canisters of FlashSystem 5030 or FlashSystem 5035 systems feature one 1 Gbps Ethernet dedicated technician port, two 10 Gbps Ethernet ports, and two 12 Gbps SAS ports for two chains of expansion enclosures.

For information about supported hardware, see the following website: www.ibm.com/support.

Node canisters can be configured for additional host I/O support via one of the following adapters:
  • A 4 port 16 Gb Fibre Channel adapter
  • A 2 port 25 Gb iSCSI (no iSER) Ethernet adapter
  • A 4 port 10 Gb Ethernet adapter (no FCoE)
  • A 4 port 12 Gb SAS adapter

Volumes

Each volume is accessible from the two nodes in an I/O group. Each host network port can recognize up to eight paths to each logical unit (LU) that is presented by the system. The hosts must run a multipathing device driver before the multiple paths can resolve to a single device. You can use fabric zoning, VLANs, or port masking to reduce the number of paths to a volume that are visible by the host. The network port types are Ethernet (iSCSI), Fibre Channel, and SAS.

Optical connections

Valid optical connections are based on the fabric rules that the manufacturers impose for the following connection methods:
  • Host to a switch
  • Back end to a switch.
  • Inter-switch links (ISLs)

Optical fiber connections can be used between a node and its switches.

Systems that use the intersystem Metro Mirror and Global Mirror functions can use optical fiber connections between the switches, or they can use distance-extender technology that is supported by the switch manufacturer.

Fibre Channel connection

The system supports shortwave Fibre Channel connections between its nodes and the switches to which they connect. To avoid communication between nodes that route across interswitch links (ISLs), connect all nodes to the same Fibre Channel or FCF switches.

No ISL hops are permitted among the nodes within the same I/O group. However, no more than three ISL hops are permitted among nodes that are in the same system though different I/O groups. If your configuration requires more than three ISL hops for nodes that are in the same system but in different I/O groups, contact your support center.

Avoid communication between nodes and storage systems that are being routed across ISLs. One ISL hop between the nodes and the storage systems is permitted. If your configuration requires more than one ISL, contact your support center.

In larger configurations, it is common to have ISLs between host systems and the nodes.