Sun Enterprise 6500/5500/4500 Systems Reference Manual

Description of the Problem

The system cannot communicate with a network if the system and the network hub are not set in the same way for the Ethernet Link Integrity Test. This problem particularly applies to 10BASE-T network hubs, where the Ethernet Link Integrity Test is optional. This is not a problem for 100BASE-T networks, where the test is enabled by default.

If you connect the system to a network and the network does not respond, use the OpenBoot command watch-net-all to display conditions for all network connections:

ok watch-net-all

For SBus Ethernet cards, the test can be enabled or disabled with a hardware jumper, which you must set manually. For the TPE and MII onboard ports on the I/O+ board, the link test is enabled or disabled through software, as shown below.

Note -

The TPE and MII ports share some circuitry so do not try to use the two ports at the same time.

Note -

Some hub designs do not use a software command to enable/disable the test, but instead permanently enable (or disable) the test through a hardware jumper. Refer to the hub installation or user manual for details of how the test is implemented.