Cisco BPX IGX IPX WAN Software

Details of the tstcon Command

Document ID: 10774

Updated: Nov 22, 2006



This document discusses the details of the tstcon command.



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tstcon Command Details

The tstcon command tests the continuity and ability of a permanent virtual circuit (PVC) to pass data through the network. The command is intrusive, and causes data on the connection that is tested to be briefly interrupted.

When the tstcon command is issued:

  • The software tells the Frame Relay PAD (FRP)/Frame Relay Module (FRM) to send a "tstframe" along with a message to the remote end that requests a remote loopback.

  • The FRP/FRM sends the "tstframe."

  • The software tells the card to issue a "getframe" to look for the response.

  • Once the "tstframe" is received, the local end declares the results:

    • If the "tstframe" is returned in its entirety, the status of the tstcon is completed and the result is "ok."

    • If the "tstframe" is not returned from the remote end, the result of the tstcon is "failed."

    • If the "tstframe" is returned from the remote end, but is incomplete or different than when it was sent, the result is "failed."

These circumstances can cause a tstcon to abort:

  • The card runs another task, such as a background test, simultaneously.

  • A tstcon is issued from the remote end at the same time, which cancels out the tstcon.

  • A manual loopback is initiated at the remote end.

  • The connection does not exist.

  • The endpoint cards of the connection failed.

  • The trunks in the path of the connection are in major alarm, such as "comm-fail," loss of signal (LOS), and so on.

  • The endpoint nodes are in "comm-break" with each other.

Note: The tstcon command was originally introduced as a debug command and is not intended as a tool for operational use.

Related Information

Updated: Nov 22, 2006
Document ID: 10774