Configuring Multipathing Interface Groups

This section provides procedures for configuring multipathing interface groups. It also describes how to make an interface a hot standby interface.

Grouping Physical Interfaces provides additional information.

Configuring Multipathing Interface Groups—Task Map

How to Configure a Multipathing Interface Group With Two Interfaces

1. Become superuser.

2. Place each physical interface into a multipathing group by typing the following command.

   # ifconfig interface-name group group-name

   For example, to place hme0 and hme1 under group test, you type the following commands:

   # ifconfig hme0 group test # ifconfig hme1 group test

3. Configure a test address for all the physical interfaces.

   • For an IPv4 test address, type the following command.

     ---

     Note –

     This step assumes that you have already configured your physical interfaces' addresses.

     ---

     # ifconfig interface-name addif ip-address <parameters> -failover deprecated up

     For example, to configure a test address on hme0 with the following configuration:

     • Address set to 19.16.85.21

     • Netmask and broadcast address set to the default value

     • -failover and deprecated options set

     You type the following command:

     # ifconfig hme0 addif 19.16.85.21 netmask + broadcast + -failover deprecated up

     You can check the configuration by typing the following:

     # ifconfig hme0:1 hme0:1: flags=9000843<UP,BROADCAST,RUNNING,MULTICAST,DEPRECATED,IPv4,NOFAILOVER> mtu 1500 index 2 inet 19.16.85.21 netmask ffffff00 broadcast 19.16.85.255

     ---

     Note –

     You must mark an IPv4 test address as deprecated to prevent applications from using the test address.

     ---

     To configure a test address on hme1 with the following configuration:

     • Address set to 19.16.85.22

     • Netmask and broadcast address set to the default value

     • -failover and deprecated options set

     Type the following command:

     # ifconfig hme1 addif 19.16.85.22 netmask + broadcast + -failover deprecated up

   • For an IPv6 test address, type the following command.

     # ifconfig interface-name inet6 -failover

     ---

     Note –

     Because you have already placed the physical interfaces with IPv4 addresses into a multipathing group, physical interfaces with IPv6 addresses are also implicitly placed in the same multipathing group. You might have placed physical interfaces with IPv6 addresses into a multipathing group first. Then physical interfaces with IPv4 addresses would have been also implicitly placed in the same multipathing group.

     ---

     For example, to configure hme0 with an IPv6 test address, you type the following command:

     # ifconfig hme0 inet6 -failover

     You can check the configuration by typing the following:

     # ifconfig hme0 inet6 hme0: flags=a000841<UP,RUNNING,MULTICAST,IPv6,NOFAILOVER> mtu 1500 index 2 inet6 fe80::a00:20ff:feb9:17fa/10 groupname test

     ---

     Note –

     You do not need to mark an IPv6 test address as deprecated to prevent applications from using the test address.

     ---

     For the second interface, hme1, type the following command:

     # ifconfig hme1 inet6 -failover

4. (Do this step only if you want to preserve the configuration across reboots.) To preserve the configuration across reboots, do the following substeps.

   • For IPv4, edit the /etc/hostname.interface file and add the following line.

     interface-address <parameters> group group-name up \ addif logical-interface -failover deprecated <parameters> up

     ---

     Note –

     This test IP address is configured only on the next reboot. If you want the configuration to be invoked in the current session, do steps 1, 2, and 3.

     ---

     For example, to create a group test with the following configuration for hme0:

     • Physical interface hme0 with address 19.16.85.19

     • A logical interface address of 19.16.85.21

     • With deprecated and -failover set

     • Sets the netmask and broadcast address to the default value

     You add the following line to the /etc/hostname.hme0 file:

     19.16.85.19 netmask + broadcast + group test up \ addif 19.16.85.21 deprecated -failover netmask + broadcast + up

     Similarly, to place hme1 under the same group test and configure a test address, type the following command:

     19.16.85.20 netmask + broadcast + group test up \ addif 19.16.85.22 deprecated -failover netmask + broadcast + up

   • For IPv6, edit the /etc/hostname6.interface file and add the following line.

     -failover group group-name up

     ---

     Note –

     This test IP address is configured only on the next reboot. If you want the configuration to be invoked in the current session, do steps 1, 2, and 3.

     ---

     For example, to create a test group for hme0 with an IPv6 address, add the following line to the /etc/hostname6.hme0 file:

     -failover group test up

     Similarly, to place hme1 under the same group test and configure a test address, add the following line to the /etc/hostname6.hme1 file:

     -failover group test up

To add more interfaces to the multipathing group, repeat steps 1 through 3. New interfaces can be added to an existing group on a live system. However, changes are lost across reboots.

How to Configure a Multipathing Group With One of the Interfaces a Standby Interface

The examples that are used in this procedure assume that hme1 will be configured as the standby interface.

A standby interface has only a test address.

1. Do steps 1 and 2 in How to Configure a Multipathing Interface Group With Two Interfaces.

2. Configure the test address on all physical interfaces by using the following substeps.

   1. For the non-standby interface, such as hme0, do step 3 in How to Configure a Multipathing Interface Group With Two Interfaces.

   2. For a standby interface, configure a test address by typing the following command.

      ---

      Note –

      A standby interface can have only a test address. A standby interface cannot have any other IP address.

      ---

      # ifconfig interface-name plumb ip-address <other-parameters> deprecated -failover standby up

      ---

      Note –

      You must set the -failover option before the standby option and the standby option before up.

      ---

      For <other-parameters>, use the parameters that are required by your configuration. See the ifconfig(1M) man page for descriptions.

      For example, to create a test address with the following configuration:

      • Physical interface hme1 as a standby interface

      • Address of 19.16.85.22

      • With deprecated and -failover set

      • Sets the netmask and broadcast address to the default value

      You type the following command:

      # ifconfig hme1 plumb 19.16.85.22 netmask + broadcast + deprecated -failover standby up

      You can check the results by typing the following:

      # ifconfig hme1 flags=69040843<UP,BROADCAST,RUNNING,MULTICAST,DEPRECATED,IPv4,NOFAILOVER,STANDBY,INACTIVE> mtu 1500 index 4 inet 19.16.85.22 netmask ffffff00 broadcast 19.16.85.255 groupname test

      For IPv6, to create a test address, type the following command:

      ifconfig hme1 plumb -failover standby up

   The INACTIVE flag indicates that this interface is not used for any outbound packets. When a failover occurs on this standby interface, the INACTIVE flag is cleared.

3. (Do this step only if you want to preserve the configuration across reboots.) To preserve the configuration across reboots, do the following substeps.

   • For IPv4, edit the /etc/hostname.interface file and add the following line.

     interface-address <parameters> group group-name up \ addif logical-interface-failover deprecated <parameters> up

     ---

     Note –

     This test IP address is configured only on the next reboot. If you want the configuration to be invoked in the current session, do steps 1 and 2.

     ---

     For example, to create a group test with the following configuration for hme0:

     • Physical interface hme0 with address 19.16.85.19

     • A logical interface address of 19.16.85.21

     • With deprecated and -failover set

     • Sets the netmask and broadcast address to the default value

     You add the following line to the /etc/hostname.hme0 file:

     19.16.85.19 netmask + broadcast + group test up \ addif 19.16.85.21 deprecated -failover netmask + broadcast + up

     Similarly, to place the standby interface hme1 under the same group test and configure a test address, type the following command:

     19.16.85.22 netmask + broadcast + deprecated group test -failover standby up

   • For IPv6, edit the /etc/hostname6.interface file and add the following line.

     -failover group group-name up

     ---

     Note –

     This test IP address is configured only on the next reboot. If you want the configuration to be invoked in the current session, do steps 1 and 2.

     ---

     For example, to create a test group for hme0 with an IPv6 address, add the following line to the /etc/hostname6.hme0 file:

     -failover group test up

     Similarly, to place the standby interface hme1 under the same group test and configure a test address, add the following line to the /etc/hostname6.hme1 file:

     -failover group test standby up

How to Display the Group to Which a Physical Interface Belongs

1. Become superuser.

2. On a command line, type the following command.

   # ifconfig interface-name

For example, to display the group name for hme0, you type the following command:

# ifconfig hme0
	hme0: flags=9000843<UP,BROADCAST,RUNNING,MULTICAST,IPv4> mtu 1500 
      index 2 inet 19.16.85.19 netmask ffffff00 broadcast 19.16.85.255
      groupname test

To display the group name for only the IPv6 instance, you type the following command:

# ifconfig hme0 inet6
	hme0: flags=a000841<UP,RUNNING,MULTICAST,IPv6> mtu 1500 index 2
        	inet6 fe80::a00:20ff:feb9:19fa/10 
        	groupname test

How to Add an Interface To a Group

1. Become superuser.

2. On a command line, type the following command.

   # ifconfig interface-name group group-name

For example, to add hme0 to the group test, you type the following command:

# ifconfig hme0 group test

How to Remove an Interface From a Group

1. Become superuser.

2. On a command line, type the following command.

   # ifconfig interface-name group ""

   The quotation marks indicate a null string.

For example, to remove hme0 from the group test, you type the following command:

# ifconfig hme0 group ""
	# ifconfig hme0
	hme0: flags=9000843<UP,BROADCAST,RUNNING,MULTICAST,IPv4> mtu 1500
        	index 2 inet 19.16.85.19 netmask ffffff00 broadcast 19.16.85.255
	# ifconfig hme0 inet6
	hme0: flags=a000841<UP,RUNNING,MULTICAST,IPv6> mtu 1500 index 2
        	inet6 fe80::a00:20ff:feb9:19fa/10 

Removing Network Adapters From Multipathing Groups provides additional information.

How to Move an Interface From an Existing Group to a Different Group

1. Become superuser.

2. On a command line, type the following command.

   # ifconfig interface-name group group-name

Placing the interface in a new group automatically removes it from any existing group.

For example, to remove hme0 from group test and place it in group cs-link, you type the following:

# ifconfig hme0 group cs-link

This command removes the interface from any existing group and then puts the interface in the group cs-link.