Configuring the cluster for iSCSI using the CLI

You need to complete several tasks to configure the cluster to work with iSCSI-attached hosts. The tasks include general tasks on the host system before you configure cluster on the SAN Volume Controller.

Before completing any iSCSI-configuration tasks on the cluster, it is important that you complete all the necessary iSCSI-related configuration on the host. Because the SAN Volume Controller supports a variety of host systems, consult the documentation for specific instructions and requirements for a particular host. For a list of supported hosts, see the Support for SAN Volume Controller (2145) Web site:

Support for SAN Volume Controller (2145) Web site

To configure a cluster for iSCSI, follow these general tasks on the host system:

Select a software-based iSCSI initiator, such as Microsoft® Windows® iSCSI Software Initiator and verify the iSCSI driver installation.
If required, install and configure a multipathing driver for the host system.

In addition, determine a naming convention for iSCSI names such as iSCSI qualified names (IQNs) for the iSCSI initiators that you are planning for the SAN Volume Controller cluster. Hosts use iSCSI names to connect to the SAN Volume Controller node. Each node, for example, has a unique IQN, and the cluster name and node name are used as part of that IQN.

Port IP addresses are the IP addresses that are used by iSCSI-attached hosts to perform I/O.

To configure a new port IP address to a specified Ethernet port of a node with an IPv4 address, enter the following command-line interface (CLI) command:
```
svctask cfgportip -node node_name | node_id -ip ipv4addr
-gw ipv4gw -mask subnet_mask -failover port_id
```
where node_name | node_id specifies the name or ID of the node that is being configured, ipv4addr is the IPv4 address for the Ethernet port, ipv4gw is the IPv4 gateway IP address, subnet_mask is the IPv4 subnet mask, and port_id specifies the Ethernet port ID (1 or 2). To view a list of ports, use the svcinfo lsportip command.

The optional -failover parameter specifies that the data is failover data, which is data that is related to the partner node. If the node that is specified is the only online node in the I/O group, the address is configured and presented by this node. When another node in the I/O group comes online, the failover address is presented by that node. If two nodes in the I/O group are online when the command is issued, the address is presented by the other node to that specified.
To configure a new port IP address that belongs to a partner node with an IPv6 address in the I/O group, enter the following CLI command:
```
svctask cfgportip -node node_name | node_id -ip_6 ipv6addr
-gw_6 ipv6gw -prefix_6 prefix -failover port_id
```
where node_name | node_id specifies the name or ID of the node that is being configured, ipv6addr is the IPv6 address for the iSCSI port, ipv6gw if the gateway address for the given IP address, prefix is the IPv6 prefix for the gateway, and port_id specifies the Ethernet port ID (1 or 2). To view a list of ports, use the svcinfo lsportip command. If the partner node is offline, the address is configured and presented by this node. When another node comes online in the I/O group, the failover address is presented by that node.

The optional -failover parameter specifies that the data is failover data, which is data that is related to the partner node. If the node that is specified is the only online node in the I/O group, the address is configured and presented by this node. When another node in the I/O group comes online, the failover address is presented by that node. If two nodes in the I/O group are online when the command is issued, the address is presented by the other node to that specified.
To remove an iSCSI IP address from a node Ethernet port, enter either of these CLI commands. The following command deletes an IPv4 configuration for the specified iSCSI Ethernet port:
```
svctask rmportip -failover 
-node node_name | node_id port_id
```
where node_name | node_id specifies the name or ID of the node with the Ethernet port that the IP address is being removed from and port_id specifies the Ethernet port ID. To list the valid values for the Ethernet port, enter the svcinfo lsportip command. The optional -failover parameter indicates that the specified data is failover data.
The following command deletes an IPv6 configuration for the specified iSCSI Ethernet port:
```
svctask rmportip -ip_6 -failover 
-node node_name | node_id port_id
```
where -ip_6 indicates that this command will remove an IPv6 configuration, node_name | node_id specifies the name or ID of the node with the Ethernet port that the IP address is being removed from, and port_id specifies the Ethernet port ID. To list the valid values for the Ethernet port, enter the svcinfo lsportip command. The optional -failover parameter indicates that the specified data is failover data.

After you configure your IP addresses, you can optionally create iSCSI aliases.