Overview

 Registration of SAN switches allows PowerVC  to use NPIV connectivity (preferred) between your virtual machines and their backend storage volumes. It also allows basic switch visibility through the PowerVC interface and shows which physical host ports are logged into which switch fabrics. In PowerVC 1.2.2, support was added for registering Cisco switches into PowerVC. Prior to that, only Brocade primary switches were supported. You can register up to two Cisco SAN switches or you can register one Brocade and one Cisco switch. Note that the switch you are registering for a fabric is referred to as the "primary" switch. You may have other switches (subordinates) on the fabric, but the primary switch maintains the zoning configuration and ensures that the zoning configuration is propagated to any subordinates as necessary.

Registering and using a Cisco SAN switch

 Registering a Cisco SAN switch is the same as registering a Brocade switch. You can use the PowerVC user interface or REST APIs to provide the switch’s IP address and credentials.  You can also provide an alternate port (the default is port 22) and VSAN information. Registration is performed using the SSH protocol. After registration, you can delete or update the port and VSAN information at any time. 

 After registering a SAN switch, an HMC, hosts, and a storage array (IBM Storwize, SVC connected storage, IBM XIV, EMC VNX or VMAX) with PowerVC,  you can deploy virtual machines. Once a virtual machine is deployed or when a data volume is attached to a virtual machine, PowerVC creates the appropriate zones in the switch.

PowerVC zoning

 When working with vSCSI connections, PowerVC will assume that there is already a valid zone created in the SAN switch between the Power Host and the storage array. Therefore, if you want to deploy virtual machines via vSCSI  or attach data volumes to virtual machines over vSCSI,  you do not have to register a SAN switch into PowerVC. However, you need to create zones in the SAN switch prior to deploying your first vSCSI based virtual machine or attaching a data volume to virtual machines using  vSCSI storage.

 When working with NPIV connections, PowerVC will expect a SAN switch to be registered. During deployment of a virtual machine or attaching volumes to virtual machines using  NPIV storage, PowerVC creates zones in the registered SAN fabric. These zones will contain the WWPNs owned by the virtual machine and target WWPNs of the storage array.

Zones are created by PowerVC in Cisco fabrics with the following methodology: The following methods are executed by PowerVC during deployment or attachment of volumes. You need not have to execute these commands but this information is provided to allow you to understand what is PowerVC is doing for you automatically.

 1. This command is run on th Cisco SAN switch using the SSH protocol : show zoneset active vsan 1 | no-more

                 In the example above, I used 1 as vsan. This is the value used while registering a Cisco switch into PowerVC.

                 From the command execution above, get a list of all active zones configured on the registered Cisco switch. This includes active zone set name.

 2. The following command set is prepared:

                 conf

                 zoneset name <active zone set name> vsan <vsan>

                 zone name <zone>

                 member pwwn <member>

                 end

 3. The command set is executed on the Cisco SAN switch to create a zone.

 4. The modified zone set is activated with this command set:

                 conf

                 zoneset activate name <active zone set name> vsan <vsan>

                 zone commit vsan <vsan>

                 end

 Where <vsan> is the value used while registering Cisco SAN switch into PowerVC.

 Zones are deleted when a VM (with boot volume configured using NPIV connectivity type) is deleted on a Power host that uses PowerVC. The following command

set is used to delete a zone :

                 conf

                 zoneset name <active zone set name> vsan <vsan>

                 no zone name <zone>

                 end

Cisco SAN switch support allows more environments to take advantage of PowerVC’s  simplified  virtualization management techniques. PowerVC's ability to create zones in SAN switches for NPIV based deployments and attachments makes it very easy to use and meet all your virtualization needs.

 Reference:

 1: Refer to http://docs.openstack.org/juno/config-reference/content/cisco-zone-driver-sys-reqs.html for the models of Cisco SAN switches that are supported by

PowerVC.  At the time of writing this, Cisco MDS 900 Family Switches and Cisco MDS NX-OS Release 6.2(9) or later are supported.