TCP port monitor - Host Unreachable alert RRS feed

  • Question

  • Hi Team,

    I created the TCP port custom monitor, But how I will generate the alert for Host Unreachable. after changing the server name or port able to generate alert for connection timeout, Connection refused and DNS resolution failure alerts.

    Please could you share the insight, In what scenario Host Unreachable alert will generate for TCP port monitor.


    Thursday, November 14, 2019 9:56 AM

All replies

  • Hi,

    You need a particulr error code returned from the TCP port probe, so that you can evaluate it as "Host Unreachable" - 2147952465.

    You can check this out here:

    TCP Port Check – Status Codes and Alert Parameters

    What you can do though is to create a MP and use the guide frm the following article to build yuour monitor in a proper way:

    SCOM Advanced Authoring: TCP Port Monitoring

    This is also a nice and interesting approach:

    Custom TCP Port Monitoring Management Pack for SCOM 2012

    Hope i could clarify this for you. Regards,

    (Please take a moment to "Vote as Helpful" and/or "Mark as Answer" where applicable. This helps the community, keeps the forums tidy, and recognizes useful contributions. Thanks!) Blog: Twitter: @StoyanChalakov

    Thursday, November 14, 2019 11:08 AM
  • Hi 

    Created the Custom management pack with same code, But still unable to replicate the alerts for host unreachable

    As I mentioned earlier, alerts for other monitors are able to test.

    My question not related to MP build, In what scenario alert will generate for host unreachable,  

    1. Changing the IP/server in MP 

    2. Changing  the Port or something else

    The status code for host unreachable are different for black box or OS ?.

    Thursday, November 14, 2019 11:28 AM
  • This is handled in the Microsoft.SystemCenter.SyntheticTransactions.TCPPortCheckProbe module, which is a "native" module; which means it is a closed-source dll and that you would need to disassemble it to see exactly what it is doing.

    • Edited by CyrAz Thursday, November 14, 2019 11:52 AM
    Thursday, November 14, 2019 11:51 AM