Messages XCOMU0505E and XCOMU0512E with RHEL9 or SuSe15

Products

• XCOM Data Transport
• XCOM Data Transport - Linux PC

Issue/Introduction

1. While certifying XCOM r12.0 on RHEL9 and SuSe15 SP04 with the new Systemd txpi sockets (txpi.socket, etc), you will receive message "#XCOMU0505E Received a Signal from TCP/IP" on the initiating system if you have initiated more transfers than the number you have specified for MaxConnections= in the txpi.socket file on the remote system.

For example:

   a. On Linux-A you initiate 64 transfers to Linux-B

   b. On Linux-B you have a value of 32 for MaxConnections= in the txpi.socket file

   Result:

        - Linux-A will receive message #XCOMU0505E for half of the initiated transfers

        - Linux-B you will only see 32 transfers come in from Linux-A.

2. Another message that you may encounter is "#XCOMU0512E Maximum remote tcp sessions reached" on the initiating Linux system when you initiate more transfers the value of MAX_REMOTE_TCP=, which defaults to 32, in the xcom.glb.

Note: The MAX_REMOTE_TCP parameter is not part of the xcom.glb file, but can be added if you want to change the value of 32.

For example:

  - Initiate 64 transfers from Linux-A

  - On Linux-B you have MaxConnections=64 in the txpi.socket file and MAX_REMOTE_TCP=32 in your xcom.glb

  Result:

    - Depending on how fast the transfers are and the resources on the systems, you can see some transfers receive message "#XCOMU0512E Maximum remote tcp sessions reached" on the initiating system(Linux-A).

Environment

XCOM Data Transport for Linux

Cause

The messages can be caused by the values of the mentioned parameters. 

Resolution

1. Review the value specified for MaxConnections= in the appropriate txpi.socket file on the initiating or remote system, depending on the transfers you are performing.

2. By default, MAX_REMOTE_TCP= has a value of 32, you may need to add/change the value of the parameter in the $XCOM_HOME/config/xcom.glb file on the initiating system. 

Additional Information

Note: Please keep in mind that message XCOMU0505E can occur due to other factors. In other words, this scenario is not the only reason why a transfers would receive the message.