System Administration Guide: Network Interfaces and Network Virtualization

ProcedureHow to Configure an IPMP Group by Using DHCP

In the current IPMP implementation, IPMP groups can be configured with Dynamic Host Configuration Protocol (DHCP) support.

A multiple-interfaced IPMP group can be configured with active-active interfaces or active-standby interfaces. For related information, see Types of IPMP Interface Configurations. The following procedure describes steps to configure an active-standby IPMP group by using DHCP.

Before You Begin

Make sure that IP interfaces that will be in the prospective IPMP group have been correctly configured over the system's network data links. For procedures to configure links and IP interfaces, see Data Link and IP Interface Configuration (Tasks). For information about configuring IPv6 interfaces, see Configuring an IPv6 Interface in System Administration Guide: IP Services.

Additionally, if you are using a SPARC system, configure a unique MAC address for each interface. For procedures, see SPARC: How to Ensure That the MAC Address of an Interface Is Unique.

Finally, if you are using DHCP, make sure that the underlying interfaces have infinite leases. Otherwise, in case of a group failure, the test addresses will expire and the IPMP daemon will then revert to link-based failure detection. Such circumstances would trigger errors in the manner the group's failure detection behaves during interface recovery. For more information about configuring DHCP, refer to Chapter 12, Planning for DHCP Service (Tasks), in System Administration Guide: IP Services.

  1. On the system on which you want to configure the IPMP group, assume the Primary Administrator role, or become superuser.

    The Primary Administrator role includes the Primary Administrator profile. To create the role and assign the role to a user, see Chapter 2, Working With the Solaris Management Console (Tasks), in System Administration Guide: Basic Administration.

  2. Create an IPMP interface.


    # ifconfig ipmp-interface ipmp [group group-name]
    

    Note –

    To configure IPv6 IPMP interfaces, use the same command syntax for configuring IPv6 interfaces by specifying inet6 in the ifconfig command, for example:


    # ifconfig ipmp-interface inet6 ipmp [group group-name]
    

    This note applies to all configuration procedures that involve IPv6 IPMP interfaces.


    ipmp-interface

    Specifies the name of the IPMP interface. You can assign any meaningful name to the IPMP interface. As with any IP interface, the name consists of a string and a number, such as ipmp0.

    group-name

    Specifies the name of the IPMP group. The name can be any name of your choice. Assigning a group name is optional. By default, the name of the IPMP interface also becomes the name of the IPMP group. Preferably, retain this default setting by not using the group-name option.


    Note –

    The syntax in this step uses the preferred explicit method of creating an IPMP group by creating the IPMP interface.

    An alternative method to create an IPMP group is implicit creation, in which you use the syntax ifconfig interface group group-name. In this case, the system creates the lowest available ipmpN to become the group's IPMP interface. For example, if ipmp0 already exists for group acctg, then the syntax ifconfig ce0 group fieldops causes the system to create ipmp1 for group fieldops. All UP data addresses of ce0 are then assigned to ipmp1.

    However, implicit creation of IPMP groups is not encouraged. Support for implicit creation is provided only to have compatible implementation with previous Solaris releases. Explicit creation provides optimal control over the configuration of IPMP interfaces.


  3. Add underlying IP interfaces that will contain test addresses to the IPMP group, including the standby interface.


    # ifconfig interface group group-name -failover [standby] up
    
  4. Have DHCP configure and manage the data addresses on the IPMP interface.

    You need to plumb as many logical IPMP interfaces as data addresses, and then have DHCP configure and manage the addresses on these interfaces as well.


    # ifconfig ipmp-interface dhcp start primary
    # ifconfig ipmp-interface:n plumb
    # ifconfig ipmp-interface:n dhcp start
    
  5. Have DHCP manage the test addresses in the underlying interfaces.

    You need to issue the following command for each underlying interface of the IPMP group.


    # ifconfig interface dhcp start
    

Example 8–1 Configuring an IPMP Group With DHCP

This example shows how to configure an active-standby IPMP group with DHCP. This example is based on Figure 7–1, which contains the following information:


# ifconfig itops0 ipmp

# ifconfig subitops0 plumb group itops0 -failover up
# ifconifg subitops1 plumb group itops0 -failover up
# ifconfig subitops2 plumb group itops0 -failover standby up

# ifconfig itops0 dhcp start primary
# ifconfig itops0:1 plumb
# ifconfig itops0:1 dhcp start

# ifconfig subitops0 dhcp start
# ifconfig subitops1 dhcp start
# ifconfig subitops2 dhcp start

To make the test address configuration persistent, you would need to type the following commands:


# touch /etc/dhcp.itops0 /etc/dhcp.itops0:1
# touch /etc/dhcp.subitops0 /etc/dhcp.subitops1 /etc/dhcp.subitops2
	
# echo group itops0 -failover up > /etc/hostname.subitops0
# echo group itops0 -failover up > /etc/hostname.subitops1
# echo group itops0 -failover standby up > /etc/hostname.subitops2
# echo ipmp > /etc/hostname.itops0