Cisco Port Adapters

Field Notice: Token Ring Inter-Switch Linking (TR-ISL) Issue on the PA-2FE-TX/FX Port Adapter

Updated August 28, 2001

August 24, 2001

Products Affected




2-Port Fast Ethernet 100Base TX Port Adapter (copper)


2-Port Fast Ethernet 100Base FX Port adapter (fiber)

Problem Description

Although TR-ISL is not available on a PA-2FE-TX/FX, the port adapter accepts the tr-isl encapsulation command. As this feature is not available on this PA, configuration of it should not be allowed.


No TR-ISL available on Port Adapters (PAs) with i82543 (Livengood) chipset.

A show controller command for following cards shows the chipset used:

'Hardware is AMD Laguna'
!--- TR-ISL fully supported on this one.

'Hardware is DEC21140A'
!--- TR-ISL supported with limit of 1500 bytes maximum transmission unit (MTU).

'Hardware is i82543 (Livengood)'
!--- TR-ISL not available. 

Problem Symptoms

After configuring TR-ISL on the PA-2FE-TX/FX, no TR-ISL traffic is seen leaving this interface.


Workaround is:

  • Use the PA-FE-TX/FX adapter

  • Use the old PA-2FEISL-TX/FX adapter (This option is not advisable; see the note below:)

    Note:?The use of the old PA-2FEISL-TX/FX adapter is not recommend because of the following:

    • Use of the PA-FE-TX/FX adapter for TR-ISL limits the MTU to 1500 bytes. For more information on this subject refer to the Token Ring Inter-Switch Link document.

    • The PA-2FEISL-TX/FX adapter is at End-Of-Life For more information on this subject refer to the Product Bulletin, No. 1225 document


To follow the bug ID link below and see detailed bug information, you must be a registered user and you must be logged in.



CSCdv16253 (registered customers only)

Need to remove TRISL configuration commands from PA-2FE-TX/FX

For More Information

If you require further assistance, or if you have any further questions regarding this field notice, please contact the Cisco Systems Technical Assistance Center (TAC) by one of the following methods: