Cisco Interface Processors

Field Notice: TN3270 Server LUs Using LU Nailing is not Working Fully with Cisco IOS 11.2BC

Revised June 8, 1999

Products Affected



Channel Interface Processor (CIP)

No remarks.

Problem Description

TN3270 server LUs using LU nailing is not working. If a client IP address is nailed to an LU or range of LUs then it cannot connect to the host. This problem is independent of whether an LU name is supplied or not.

This problem first appeared in Cisco IOS release 11.2(18)BC with associated CIP microcode 24-11. The problem still exists in CIP microcode 24-12.


"TN3270 Server Client to LU Nailing" is also known as "Client IP Address Nailing," a feature that allows the network administrator to restrict what client IP addresses can connect to particular LUs. This lets clients from traditional TN3270 (non-TN3270E) devices connect to specific LUs, thus overcoming the limitation of TN3270 devices in that they cannot specify a "CONNECT LU." This is achieved by configuring the IP address to LU mappings in the TN3270 server. This feature is also useful for TN3270E clients because in many instances it is preferable to do the configuration centrally at the router rather than at the client.

More information on this feature is available in the CCO document "TN3270 Server Client to LU Nailing."

This problem is seen only in CIP microcodes 24-11 and 24-12 as well as the associated Cisco IOS software 11.2BC. This problem does not occur in other versions of the software.

This defect has Cisco bug ID CSCdm36117 (registered customers only) .

Problem Symptoms

TN3270 clients will be unable to connect with the CIP TN3270 server.

The output from a CIP console TN3270 capture will look as follows:

%CIP: slot4 [bad telnet connect]13[ipAddrClient][tcpPortCl
%CIP: slot4 ----ient]0x40C:[connectReasonCode]0xE:[tn3270eDeviceType]IBM
%CIP: slot4 -----3278-5-E:[tn3270eDeviceName]:[tn3270eSubErr]no-naill:

If used, a similar message will be seen on CiscoView.


The workaround for this problem is to remove LU nailing and restart the TN3270 server. Only removing the LU nailing command and not restarting the TN3270 server is not sufficient to workaround the problem. An alternative workaround is to use dynamic LU build. This still works with LU nailing.

The permanent resolution to this problem is included in a software fix incorportated into CIP microcode 24-13 which is due for release along with Cisco IOS 11.2(19)BC the week beginning 19 July 1999.

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:

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