TN520 iSeries HMC Console Hangs in AP r11.5 base

Document ID : KB000031778
Last Modified Date : 14/02/2018
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Occasionally, TN5250 connections hosted by the iSeries HMC would hang.

Root Cause:

This hang condition could be caused by a variety of conditions, including the connection being idle for longer than 60 seconds. 


Several code fixes were made in order to ensure that the communication packets sent to the host were formatted correctly. An additional configuration change is required to turn off TN5250 protocol keepalive packets, which the iSeries HMC does not handle properly.

The code fix mentioned above is currently available in ap11507ServerPatch.exe (Patch 7) located at the following FTP site:

This FTP site has anonymous login so you do not need any credentials to access the patches and download the files. Also, Patch #7 is cumulative, so it includes all fixes from earlier patches.

With respect to the additional configuration change required to turn off TN5250 protocol keepalive packets mentioned in the first paragraph of this solution, please download the attached KeepAlive.txt and use the following instructions to apply them:

KeepAlive.txt contains the command needed to update your Session Definition Set to disable the TN5250 KeepAlive option for the specified AS/400 HMC session. Just rename this .txt file to .bat and you should be able to execute this file. The file has the following single command:

asomaputil sc_Session~Definition~Set~1.apm rw SessSet\usilihm1\CustSessSet\CoaxSess\KeepAlive 0 d

The above command makes the following assumptions:
•    The name of your active Session Definition Set is “Session Definition Set 1”. If you have named your active Session Definition Set to a non-default value, then you will need to change the first parameter of this command to be “sc_Name~Of~Session~Definition~Set.apm”.
•    The name of your AS/400 HMC session is “usilihm1”. This section will have to be changed to the name of your AS/400 HMC session.

In summary,  you will need to install patch 7 of AP r11.5 ( in addition to running the above command in order to avoid freezing of the HMC TN5250 console. Again, once AP r11.5 SP1 is GA, you can use the appropriate Configuration Manager dialog to enable or disable this KeepAlive setting.

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