Under the Access category in the main navigation menu, users can configure hosts (Windows, Linux, or UNIX) for storage access. VMware hosts can be configured on the VMware (Hosts) page. Before a network host can access block storage, the user must define a configuration for the host and associate it with a storage resource. Access to NFS Shares can be restricted to certain hosts. When configured, SMB file systems can automatically be accessed by authorized users. Users can use the Hosts page, as shown in Figure 18, to configure host configurations. This can be done on an individual host-by-host basis or through subnet and netgroup configurations that allow access to multiple hosts or network segments. For block resources, before the user starts to configure a host, the user should ensure that initiator interfaces are configured, and initiator registration is completed. After a host configuration is completed, users can go to the properties of a storage resource and specify the hosts from which they want the resource to be accessed.
In Dell Unity OE version 4.4 and later, Unisphere prevents the user from deleting a block resource that has host access assigned to it. To delete the host-accessible block resource, the user first needs to remove host access before the block resource can be deleted.
To remove host access from multiple resources, the user can select the multiple resources and click the More Actions > Modify Host Access action, as shown in Figure 19.
In Dell Unity OE version 5.0, the user can assign multiple LUNs to multiple Hosts at the same time. In addition, a Merge operation is also available. Merge provides access to the list of hosts to the selected LUNs. For example, if some LUNs use Host1 and Host2, and others use Host5 and Host6, the Modify Host Access window will list all the hosts (Host1, Host2, Host5, and Host6) after the merge operation completes.
In Dell Unity OE version 5.1 and later, users can logically group hosts and block resources within a host group. Host groups can be created and managed from the Host Groups tab, as shown in Figure 20, and help to streamline host/resource access operations. A host group can be one of two types, General and ESX, which is persistent for the life of the group. A General type host group allows one or more non ESXi hosts and LUNs to be grouped. ESX host groups allow VMware ESXi hosts to be grouped with LUNs and/or VMFS datastores.
When a host is added to a host group, the host is automatically mapped to all resources assigned to the group. When adding a host to the group a merge option is also available, which maps all block resources assigned to the host to the host group and all hosts in it. If merge is not used, the resource attached to the host will be displayed within the host group, but access is restricted and remains unchanged. When a resource is added to the group, it is automatically mapped to all hosts within the group. Configuring host access using the resource creation wizard or on an existing resource remains unchanged.