84 CHAPTER 5: PROBLEM SOLVING3 Power cycle the unit. To do this, remove and reconnect the AC mainssupply. If the unit has no AC main supply, remove and reconnect the DCRPS supply.4 If another fan failure warning message is generated via the CommandLine Interface or the Web interface, return the unit to 3Com.Unit fails, no SNMP fan failure message is received1 Power cycle the unit. To do this, remove and reconnect the AC mainssupply. If the unit has no AC mains supply, remove and reconnect the DCRPS supply.2 Check the command line interface (display logbuffer command)to determine whether a thermal shutdown has occurred.3 If no, return the unit:If yes, check that:■ The air vents are not obstructed.■ The ambient temperatures and environmental conditions meet thosespecified in Appendix C on page 127.4 Power cycle the unit. If a further thermal shutdown occurs, and allenvironmental conditions are satisfactory, return the unit to 3Com.Error message indicating that the SFP transceiver is invalidThe switch has identified that the SFP does not meet the minimumrequirements for the switch and has disabled the port. To correct thisproblem, completely remove the SFP and replace it with a 3Comapproved SFP. See “Approved 1000BASE-X SFP Transceivers” on page 47and “Approved 100BASE-X SFP Transceivers” on page 48.Error message indicating that the SFP transceiver is faultyTo correct this problem, completely remove the SFP and then reinsert it.Alternatively, insert another identical SFP. If the problem persists, contact3Com Technical Support.SolvingCommunicationProblemsIf you experience communication problems with the switch, ensure that:■ The switch IP address and management VLAN ID has been configured.
