TS7700 Grid

Edit online

A TS7700 Grid refers to two or more physically separate TS7700 Clusters connected to one another by using a customer-supplied Internet Protocol network. A TS7700 Grid can contain disk-only clusters that do not attach to a physical tape library, clusters that do attach to a physical tape library, or a combination of both.

Note: TS7740s and TS7720s must not be members of the same grid.

The TCP/IP infrastructure that connects a TS7700 Grid is known as the Grid Network. The grid configuration is used to form a disaster recovery solution and provide remote virtual volume replication. The term grid refers to the code and functionality that provides replication and management of virtual volumes and their attributes in cluster configurations. A Grid can be used to form disaster recovery and high availability solutions. A disaster recovery solution is achieved when multiple clusters are geographically distant from one another. A high availability solution is achieved when multiple clusters are in close proximity to one another.

The clusters in a TS7700 Grid can, but do not need to be, geographically dispersed. In a multiple-cluster grid configuration, two clusters are often located within 100 km of one another, while the remaining clusters can be located more than 1,000 km away. This provides both a highly available and redundant regional solution while also providing a remote disaster recovery solution outside of the region. Any TS7700 Cluster can also be in relatively distant proximity to one another; discuss this type of configuration with your IBM® representative for any planning considerations. Any TS7700 Clusters in relatively close proximity would typically use an immediate mode copy policy. TS7700 Clusters in relatively distant proximity would typically use a deferred mode copy policy.

Refer to Figure 3 for an illustration of a typical multi-cluster grid configuration.

Each TS7700 Cluster provides FICONFICON® host attachments and between 256 and 496 virtual tape device addresses, depending on the installed features. The clusters in a Grid configuration are connected together through dual 1 Gb Ethernet links. The links use standard 1000 Base-T adapters for CAT-5E or CAT6 (CAT6 is highly recommended) balanced copper cabling or standard shortwave adapters for multimode fiber cable. Each grid Ethernet adapter contains two 1 Gb ports. You can use both ports on each adapter, for four total 1 Gb Ethernet grid links. The same Ethernet links are used for the replication of data between clusters. They pass control information and access between a local cluster's virtual tape device and a virtual volume's data in a remote cluster's TS7700 Cache. For a multiple-site grid Ethernet connection, you have a choice of the following adapters:

1 Gb copper Ethernet, 10/100/1000 Base-TX: This adapter conforms to the IEEE 802.3ab 1000 Base-T standard, which defines Gb Ethernet operation over distances up to 100 meters by using four pairs of CAT-6 copper cabling.
1 Gb dual port copper Ethernet: This adapter is a full duplex, dual ported, Gb Ethernet adapter that can be configured to run each port at 10, 100, or 1000 Mbps data rates. The adapter conforms to the IEEE 802.3ab 1000 Base-T standard.
Note: Only the primary port can be used for the grid network unless FC 1034, Enable dual port grid connection is installed. Refer to the topic Feature details in the Related information section for feature code prerequisites and other requirements.
10 Gb Optical longwave: This adapter supports a maximum of 10 kilometers of 1310 nm, 9μm, single-mode fiber optic cable. It conforms to the IEEE 802.3ae standard. This adapter requires 9μm single-mode fiber optic cables and uses an LC connector to connect to network infrastructure components.

Note: Each link requires a unique, customer assigned IP address.

Ethernet activity is specific to each adapter and port pairing. As a result, clusters in a grid do not necessarily all require the same number of ports. Clusters with 10 Gb, four 1 Gb, and two 1 Gb Ethernet connections can be part of the same grid configuration. Use of the second 1 Gb Ethernet port present in both grid Ethernet adapters is supported. This results in availability of four total 1 Gb ports for TS7700 Grid interconnections. It requires two dual-ported adapters and is activated by using FC 1034, Enable dual port grid connection.

You can use Selective Device Access Control to tune the use of grid links. For more information, see Selective device access control in the Related information section.