Configuring shared interfaces

Prerequisites for configuring shared interfaces

To configure a pair of shared interfaces so that one can replace the other if one storage system fails and is taken over, you must have available the following items:

Two interfaces, one installed on each node in the cluster
Two IP addresses, the address of one interface on each node in the cluster

Emulated LAN considerations

For LANE, when an adapter is shared, an Emulated LAN cannot be configured more than once on the adapter after takeover. This means that if both nodes in a cluster pair are on the same Emulated LAN, each node needs a minimum of two ATM cards to support full takeover.

Configuring shared interfaces

To configure a pair of shared interfaces for takeover, complete the following steps.

Step	Action
1	Enter the following command on the command line of both nodes in a cluster and in the /etc/rc file of both nodes, so that the command is permanent: ifconfig interface local_address partner partner_address {other_options} interface is the name of the local interface. local_address is the IP address of the local interface. partner_address is the IP address or interface name that the local interface services when the local node takes over the other node in the cluster. other_options denotes whatever other options are needed to correctly configure the interface in your network environment. For more information about the `ifconfig` command, see the Network Management Guide and the na_ifconfig man page. Example `ifconfig e0 199.9.204.255 partner 199.9.204.254` Note When you configure virtual interfaces for takeover, you must specify the interface name and not the IP address.
2	If you want to configure your interfaces for automatic takeover in case of NIC failure, follow the steps outlined in Configuring VIFs or interfaces for automatic takeover.

Step

Action

Enter the following command on the command line of both nodes in a cluster and in the /etc/rc file of both nodes, so that the command is permanent:

ifconfig interface local_address partner partner_address 
{other_options}

interface is the name of the local interface.

local_address is the IP address of the local interface.

partner_address is the IP address or interface name that the local interface services when the local node takes over the other node in the cluster.

other_options denotes whatever other options are needed to correctly configure the interface in your network environment.

For more information about the ifconfig command, see the Network Management Guide and the na_ifconfig man page.

Example

ifconfig e0 199.9.204.255 partner 199.9.204.254

Note
When you configure virtual interfaces for takeover, you must specify the interface name and not the IP address.

If you want to configure your interfaces for automatic takeover in case of NIC failure, follow the steps outlined in Configuring VIFs or interfaces for automatic takeover.

Emulated LAN example

A cluster pair might be configured with Emulated LANs as follows.

Storage system and adapter	Interfaces and Emulated LANs	Storage system and adapter	Interfaces and Emulated LANs
appliance1-a4	el0 default el1 nineKMTU	appliance1-a5	el2 eighteenKMTU
appliance2-a4	el0 default el1 nineKMTU	appliance2-a5	el2 eighteenKMTU

To achieve full takeover, you would use these commands on both nodes:

ifconfig a4 partner a5

ifconfig a5 partner a4

Note
If a4 and partner a5 are configured with common Emulated LANs, a4 does not take over those Emulated LANs.

Virtual interface example

The following is an example of a virtual interface configuration command:

ifconfig vif0 partner vif0

VLAN interface example

The following is an example of a VLAN interface configuration command:

ifconfig e9-100 partner e7-100