Rocket iCluster

Tracking iCluster Communications Messages

  • 1.  Tracking iCluster Communications Messages

    Posted 09-21-2020 15:57
    Edited by William Shubin 09-21-2020 15:58

    If you are having communications issues, you can see some of the internal communication messages that are generated by iCluster behind the scenes to assist in problem resolution. Just create a new message queue on the node that appears to be having the problem called DMKMSGQ in the iCluster product library (almost always ICLUSTER).


    Then after a period of time, use DSPMSGQ DMKMSGQ to display the messages and send them to support. You can keep the message queue active if you like or delete it once the problem is solved.

    Here is the entire list of steps to obtain and review iCluster communication issues:


    1. Screen print of option 7 from iCluster main menu
    2. Document any TCP changes or firewall changes recently
    3. If IP changes occurred, check NETSTAT *CNN ensure all ports for DMCLUSTER user are using specified IP address. Check source and target.
    4. Check NETSTAT *CNN, sort by user and verify all DMCLUSTER ports for retransmissions (do on source and target)
    5. Create DMKMSGQ in iCluster product library. Recycle the iCluster nodes and subsystem, this will unlock additional communication messages
    6. Review all joblogs for a group at time of failure for source and target, try to verify which system is failing first by failures and time stamps
    7. Review eventlog with communication type messages specified
    8. Attempt 'ping' command source to target, target to source, this is a basic type of communication outside the iCluster product
    9. Attempt 'telnet' command from source to target, target to source to verify if it completes. Another test outside the iCluster product to help verify communications.
    10. Attempt 'ftp' test to transfer data to backup or back to source outside the iCluster product, note transfer rate and compare to expected rate for your bandwidth.
    11. Attempt 'HAPNGTCP' command source to target, target to source, this is a more accurate representation of replication.

    William Shubin
    Rocket Software