TCP reassemble queue limit hits

TCP maintains Out-of-Order queue to keep the OOO packets in the TCP communication. This setting impacts Citrix ADC memory if the queue size is long as the packets need to be kept in runtime memory.

This queue size needs to be kept at optimized level based on the network and application characteristics.

Using the TCP reassemble queue limit hits indicator, you can view if the Out-of-Order packets on a TCP connection exceed the configured out of order packet queue size.

Click the TCP reassemble queue limit hits tab to view the issue details.

TCP reassemble queue limit hits

The Recommended Actions to troubleshoot the issue are:

  • Review the traffic and blacklist the source if it is an attack

  • If this behavior is an expected network behavior, then update the out-of-order packets size value on TCP profile. For more information, see TCP Optimization

  • If it is just a temporary network glitch, then no further action is required

Under Details, you can view:

  • The time that occurred the anomaly

  • Total occurrences

  • The anomaly severity such as low, medium, and high

  • The detection message indicating the current TCP profile and oooQsize settings