This article discusses whether it is advisable to install Ethernet Update 1.0 on your Macintosh computer. It also offers a procedure for determining whether a Macintosh computer is affected by the issue that Ethernet Update 1.0 resolves.

It is not necessary to install this update unless you are experiencing reliability issues with your Ethernet networking configuration.

Ethernet Update 1.0 addresses an issue where a Macintosh in certain rare network configurations may continue to transmit data but not receive data. Manually putting the Macintosh to sleep and then waking it, or restarting the computer enables it to temporarily reestablish network connectivity. After a period of time, which varies by topology and infrastructure, the computer again ceases to receive packets. The computer functions normally on isolated networks.

Products Affected

• iMac (Slot Loading) computers manufactured since early November 1999
• Power Mac G4 (AGP Graphics) computers manufactured since late November 1999
• PowerBook (FireWire)
• iBook (pre-FireWire)

Determining if the Issue Exists
The existence of the issue described in this article can be determined with the SNMP Administrator program. Follow these steps to install it:

1. Perform a custom installation of system software from the Mac OS 9 CD, installing only the SNMP agent.
2. Copy the SNMP Administrator program from the CD to the hard disk. (Mac OS 9 CD: CD Extras: Network Extras: OT Extras: SNMP Admin: SNMP Administrator)
3. Restart the computer.

When you suspect your Macintosh has lost connectivity to the network, then:

1. Open the SNMP Administrator. The Community List dialog box appears.
2. Open the "public" community in the Community List dialog box.
3. Click the Interface Agent tab; the ifNumber and ifTab are shown.
4. Double-click ifTable (the name, not the tab); the Variables Values window appears.
5. Scroll through the window until you locate ifInOctets and ifOutOctets.
6. Write down the Value for the ifInOctets and ifOutOctets.
7. If AppleTalk is active, open the Chooser. Click the AppleShare icon, then the LaserWriter icon, and perhaps even the AppleShare icon once again, then close the Chooser. Alternatively, open a web browser and load a page such as www.apple.com . (Note that these actions should not display AppleShare servers or LaserWriter printers in the Chooser, nor display the web site you entered.)
8. Click the SNMP Administrator window to make it active.
9. Click Update.
10. Record the ifInOctets and ifOutOctets counts again.
11. Compare the ifInOctets and ifOutOctets values:
• If the ifInOctets count does not increase in value after the fault occurs and the ifOutOctets does increase in value, make sure you performed steps 7 through 9. If you did perform steps 7 through 9 and the IfInOctets did not increase in value, then this computer has encountered this Ethernet issue and would benefit from installing the Apple Ethernet Update 1.0.
• If the ifInOctets and ifOutOctets values both continue to increase in value then this Macintosh has not encountered this issue, but instead has encountered some other difficulty. It may require additional network troubleshooting. You may wish to search the Knowledge Base for troubleshooting tips or for other known issues such as with the Spanning Tree Protocol:
  Article 30922: " Spanning Tree Protocol: AppleTalk Issues "

After conducting this test with SNMP Administrator, you may wish to remove or disable the following extensions if you don't intend to routinely use SNMP Administrator or other SNMP Management Consoles or tools:

• Open Transport SNMP
• OpenTptSNMPLib