SolvingHardware Problems 47
The Unit LED is flashing green
The Switch unit physically forms a stack with other Switch 4400 units, but
cannot be managed as part of that stack because one or more units have
not been upgraded to software version 2.0 or later.You must upgrade
each unit in the stack to this software version, which is available on the
CD-ROM that accompaniesyour Switch.
Solving HardwareProblems
In the rare event of your Switch unit experiencing a hardware failure,
refer to the list of suggested solutions below.
An expansion module is installed and the unit will not power up
Ensure that the expansion module is fully seated in the slot and the
connectors are engaged so that the securing screws can be tightened.
An SNMP fan fail trap is received
1Power off the unit.
2Check that the air vents are not obstructed.
3Power cycle the unit. Todo this, remove and reconnect the AC mains
supply.If the unit has no AC main supply, remove and reconnect the DC
RPS supply.
4If a further fan fail trap is received, return the unit.
Unit fails, no SNMP fan fail trap is received
1Power cycle the unit. Todo this, remove and reconnect the AC mains
supply.If the unit has no AC mains supply, remove and reconnect the DC
RPS supply.
2Checkthecommandlineinterface(system summary command)to
determine whether a thermal shutdown has occurred.
3If no, return the unit:
If yes, check that:
■The air vents are not obstructed.
■The ambient temperatures and environmental conditions meet those
specifiedinAppendixC.
4Power cycle the unit. If a further thermal shutdown occurs, and all
environmental conditions are satisfactory,return the unit to 3Com.
17204ua.book Page 47 Monday, August 13, 2001 11:28 AM