Planning for a direct-attached configuration

A direct-attached configuration dedicates entire port bandwidth to be used for a specific connection. Planning must account for the volume of expected traffic before you decide how many ports are used in a direct-attached configuration.

The Lenovo Storage V series system offers multiple options in deciding how to create a direct-attached configuration. Because of the bandwidth requirements when you are using a direct-attached configuration, it is important to determine the volume of expected traffic in deciding the number of required ports. For example, if a Lenovo Storage V series to Lenovo Storage V series direct-attached link is configured between nodes, then the link might carry intra-node traffic such as FlashCopy data. Hence, enough Lenovo Storage V series to Lenovo Storage V series bandwidth needs to be available so that it can carry all possible intra-node traffic without any bandwidth bottleneck.

The following guidelines are provided for direct-attached configurations.
  1. Fibre Channel direct attachment to host systems:

    Lenovo Storage V series allows direct attachment connectivity between its Fibre Channel ports and host ports. Host systems can be connected to 8 Gb or 16 Gb Fibre Channel ports on Lenovo Storage V series. No special configuration is required for host systems that are using this configuration.

  2. Fibre Channel direct attachment between nodes in a Lenovo Storage V series system:

    Direct connection of Lenovo Storage V series Fibre Channel ports without using a Fibre Channel switch is supported. Such direct connections between Lenovo Storage V series nodes might be useful in small configurations where there is no Fibre Channel switch. It can also be used to connect nodes in the same I/O group to provide a dedicated connection for mirroring the fast write cache data. Ensure that sufficient bandwidth is provisioned between nodes to accommodate all the intra-node traffic.

Lenovo Storage® V7000 Gen2 supports 16 Gb Fibre Channel ports. This platform supports Fibre Channel direct attachment on all 16 Gb ports.