IP Interface Configuration (Tasks)

This section describes basic configuration procedures on an IP interface. The following table describes configuration tasks and maps these tasks to their corresponding procedures.

Table 8-1 Configuring IP Interfaces (Task Map)

SPARC: How to Ensure That the MAC Address of an Interface Is Unique

Some applications require every interface on a host to have a unique MAC addresses. However, every SPARC based system has a system-wide MAC address, which by default is used by all interfaces. Here are two situations where you might want to configure the factory-installed MAC addresses for the interfaces on a SPARC system.

• For link aggregations, you should use the factory-set MAC addresses of the interfaces in the aggregation configuration.

• For IPMP groups, each interface in the group must have a unique MAC address. These interfaces must use their factory-installed MAC addresses.

The EEPROM parameter local-mac-address? determines whether all interfaces on a SPARC system use the system-wide MAC address or their unique MAC address. The next procedure shows how to use the eeprom command to check the current value of local-mac-address? and change it, if necessary.

1. Become an administrator.

   For more information, see How to Obtain Administrative Rights in System Administration Guide: Security Services.

2. Determine whether all interfaces on the system currently use the system-wide MAC address.

   # eeprom local-mac-address?
   local-mac-address?=false

   In the example, the response to the eeprom command, local-mac-address?=false, indicates that all interfaces do use the system-wide MAC address. The value of local-mac-address?=false must be changed to local-mac-address?=true before the interfaces can become members of an IPMP group. You should also change local-mac-address?=false to local-mac-address?=true for aggregations.

3. If necessary, change the value of local-mac-address? as follows:

   # eeprom local-mac-address?=true

   When you reboot the system, the interfaces with factory-installed MAC addresses now use these factory settings, rather than the system-wide MAC address. Interfaces without factory-set MAC addresses continue to use the system-wide MAC address.

4. Check the MAC addresses of all the interfaces on the system.

   Look for cases where multiple interfaces have the same MAC address. In this example, all interfaces use the system-wide MAC address 8:0:20:0:0:1.

   ifconfig -a
   lo0: flags=1000849 <UP,LOOPBACK,RUNNING,MULTICAST,IPv4> mtu 8232 index 1
         inet 127.0.0.1 netmask ff000000  
   hme0: flags=1004843 <UP,BROADCAST,RUNNING,MULTICAST,IPv4> mtu 1500 index 2
         inet 10.0.0.112 netmask ffffff80 broadcast 10.0.0.127
         ether 8:0:20:0:0:1 
   ce0: flags=1004843 <UP,BROADCAST,RUNNING,MULTICAST,IPv4> mtu 1500 index 2
         inet 10.0.0.114 netmask ffffff80 broadcast 10.0.0.127
         ether 8:0:20:0:0:1 
   ce1: flags=1004843 <UP,BROADCAST,RUNNING,MULTICAST,IPv4> mtu 1500 index 2
         inet 10.0.0.118 netmask ffffff80 broadcast 10.0.0.127
         ether 8:0:20:0:0:1

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   Note - Continue to the next step only if more than one network interface still has the same MAC address. Otherwise, go on to the final step.

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5. If necessary, manually configure the remaining interfaces so that all interfaces have unique MAC address.

   Specify a unique MAC address in the /etc/hostname.interface file for the particular interface.

   In the example in Step 4, you would need to configure ce0 and ce1 with locally administered MAC addresses. For example, to reconfigure ce1 with the locally administered MAC address 06:05:04:03:02, you would add the following line to /etc/hostname.ce1:

   ether 06:05:04:03:02 

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   Note - To prevent any risk of manually configured MAC addresses conflicting with other MAC addresses on your network, you must always configure locally administered MAC addresses, as defined by the IEEE 802.3 standard.

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   You also can use the ifconfig ether command to configure an interface's MAC address for the current session. However, any changes made directly with ifconfig are not preserved across reboots. Refer to the ifconfig(1M) man page for details.

6. Reboot the system.