openSolaris 2008 - Maintaining IPMP Groups - System Administration Guide: IP Services

Maintaining IPMP Groups

This section contains tasks for maintaining existing IPMP groups and the interfaces that compose those groups. The tasks presume that you have already configured an IPMP group, as explained in Configuring IPMP Groups.

How to Display the IPMP Group Membership of an Interface

On the system with the IPMP group configuration, become superuser or assume an equivalent role.
Roles contain authorizations and privileged commands. For more information about roles, see Configuring RBAC (Task Map) in System Administration Guide: Security Services.
Display information about the interface, including the group to which the interface belongs.
```
# ifconfig interface
```
If applicable, display IPv6 information for the interface.
```
# ifconfig interface inet6
```

Example 31-5 Displaying Physical Interface Groups

To display the group name for hme0, you would type the following:

# ifconfig hme0
    hme0: flags=9000843<UP,BROADCAST,RUNNING,MULTICAST,IPv4> mtu 1500 
      index 2 inet 192.168.85.19 netmask ffffff00 broadcast 192.168.85.255
      groupname testgroup1

To display the group name for only the IPv6 information, you would type the following:

# ifconfig hme0 inet6
    hme0: flags=a000841<UP,RUNNING,MULTICAST,IPv6> mtu 1500 index 2
            inet6 fe80::a00:20ff:feb9:19fa/10 
            groupname testgroup1

How to Add an Interface to an IPMP Group

On the system with the IPMP group configuration, 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.
Add the interface to the IPMP group.
```
# ifconfig interface group group-name
```
The interface specified in interface becomes a member of IPMP group group-name.

Example 31-6 Adding an Interface to an IPMP Group

To add hme0 to the IPMP group testgroup2, you would type the following command:

# ifconfig hme0 group testgroup2
  hme0: flags=9000843<UP ,BROADCAST,RUNNING,MULTICAST,IPv4,NOFAILOVER> mtu 1500 index 2
  inet 192.168.85.19 netmask ff000000 broadcast 10.255.255.255
  groupname testgroup2
  ether 8:0:20:c1:8b:c3

How to Remove an Interface From an IPMP Group

When you execute the ifconfig command's group parameter with a null string, the interface is removed from its current IPMP group. Be careful when removing interfaces from a group. If some other interface in the IPMP group has failed, a failover could have happened earlier. For example, if hme0 failed previously, all addresses are failed over to hme1, if hme1 is part of the same group. The removal of hme1 from the group causes the in.mpathd daemon to return all the failover addresses to some other interface in the group. If no other interfaces are functioning in the group, failover might not restore all the network accesses.

Similarly, when an interface in a group needs to be unplumbed, you should first remove the interface from the group. Then, ensure that the interface has all the original IP addresses configured. The in.mpathd daemon tries to restore the original configuration of an interface that is removed from the group. You need to ensure that the configuration is restored before unplumbing the interface. Refer to What Happens During Interface Failover to see how interfaces look before and after a failover.

On the system with the IPMP group configuration, 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.
Remove the interface from the IPMP group.
```
# ifconfig interface group ""
```
The quotation marks indicate a null string.

Example 31-7 Removing an Interface From a Group

To remove hme0 from the IPMP group test, you would type the following command:

# ifconfig hme0 group ""
    # ifconfig hme0
    hme0: flags=9000843<UP,BROADCAST,RUNNING,MULTICAST,IPv4> mtu 1500
    index 2 inet 192.168.85.19 netmask ffffff00 broadcast 192.168.85.255
    # ifconfig hme0 inet6
    hme0: flags=a000841<UP,RUNNING,MULTICAST,IPv6> mtu 1500 index 2
    inet6 fe80::a00:20ff:feb9:19fa/10

How to Move an Interface From One IPMP Group to Another Group

You can place an interface in a new IPMP group when the interface belongs to an existing IPMP group. You do not need to remove the interface from the current IPMP group. When you place the interface in a new group, the interface is automatically removed from any existing IPMP group.

On the system with the IPMP group configuration, 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.
Move the interface to a new IPMP group.
```
# ifconfig interface group group-name
```
Placing the interface in a new group automatically removes the interface from any existing group.

Example 31-8 Moving an Interface to a Different IPMP Group

To change the IPMP group of interface hme0, you would type the following:

# ifconfig hme0 group cs-link

This command removes the hme0 interface from IPMP group test and then puts the interface in the group cs-link.