Typical Networking

Context

Install multipathing software for a network with more than two links to help select and manage paths between the storage system and application servers. This section uses the multipathing software developed by Huawei, the UltraPath, as an example. For details on how to install and configure UltraPath, see OceanStor UltraPath User Guide.

If the UltraPath version is 21.1.0 or later and SmartKit whose version is V2R5C00RC10 or later is installed, you can use SmartKit to quickly install UltraPath. For details about the installation procedure, see Using SmartKit to Install UltraPath.

Dual-Link Direct-Connection Networking

Dual-link direct connection is the simplest, most inexpensive, and most reliable storage network connection. Figure 2-6 shows a typical dual-link direct-connection networking topology.

Figure 2-6 Dual-link direct-connection networking

In this networking mode, two paths are established between the application server and storage controllers for redundancy. The path between the application server and the LUN's controller is the optimum one and the other path is standby.

In normal cases, the UltraPath selects the optimum path for data transfer. If the optimum path is down, the standby path is used. After the optimum path recovers, UltraPath switches data transfer back to the optimum path again.

Multi-Link Single-Switch Networking

In the multi-link single-switch networking mode, one switch is added on the basis of dual-link direct connection to improve data access and forwarding capabilities. Figure 2-7 shows a typical multi-link single-switch networking topology.

Figure 2-7 Multi-link single-switch networking

A switch expands host ports to improve the access capability of the storage system. Besides, a switch extends the supported transfer distance so that a remote application server can connect to the storage system through the switch. Since only one switch is available in this networking mode, it is vulnerable to single points of failure.

There are four paths between the application server and storage system. The two paths between the application server and LUN's controller are the optimum paths, and the other two paths are standby. In different scenarios, the UltraPath works as follows:

• In normal cases, the UltraPath selects the two optimum paths for data transfer.
• If one optimum path is faulty, UltraPath selects the other optimum path for data transfer.
• If both optimum paths are faulty, UltraPath uses the two standby paths for data transfer. After an optimum path recovers, UltraPath switches data transfer back to the optimum path again.

Multi-Link Dual-Switch Networking (with Key Management Servers Configured)

In this networking mode, in addition to the dual-switch forwarding capability, a dual key management server cluster provides secure storage services without compromising the storage performance. Figure 2-8 shows a typical multi-link dual-switch networking topology with dual key management servers configured as a cluster.

Figure 2-8 Multi-link dual-switch networking (with a dual key management server cluster)

With two switches, the network is protected against single points of failure, which improves the network reliability.

There are four paths between the application server and storage system. The UltraPath software works in the same way as that in the multi-path single-switch networking mode.

Two key management servers are configured. When one server becomes faulty, services are switched on to the other server automatically, ensuring uninterrupted service data encryption/decryption.

Multi-Link Dual-Switch Networking (with No Key Management Servers Configured)

In this networking mode, one switch is added on the basis of multi-link single-switch connection, achieving the dual-switch forwarding capability. Figure 2-9 shows a typical multi-link dual-switch networking topology with no key management servers configured.

Figure 2-9 Multi-link dual-switch networking (with no key management servers)

With two switches, the network is protected against single points of failure, which improves the network reliability.

There are four paths between the application server and storage system. The UltraPath software works in the same way as that in the multi-path single-switch networking mode.