TCP/IP Stack Layers History workspace

The TCP/IP Stack Layers History workspace displays historical performance data for the layers of the TCP/IP stack.

This workspace displays the most recent 24 hours of historical data by default. This workspace can be displayed by right-clicking on the TCP/IP Stack Navigator item.

Short Term History support is an optional feature that must be enabled for this workspace to display attribute and metric values. If this workspace does not contain data, you will see message KFWITM220E Request failed during execution displayed in the Tivoli Enterprise Portal message area. Contact your system administrator to request that historical collection be started for this attribute group.

Notes:

  1. If the address space being monitored is running on z/OS v1.11 or earlier, the values for these attributes are retrieved using SNMP. If the address space being monitored is running on z/OS v1.12 or later, the values for these attributes are retrieved using the z/OS Communications Server callable network management interface (NMI).
  2. If you are viewing this workspace on z/OS v1.12, non-strategic interfaces report only status information. Performance-related attributes show a value of zero (0). The strategic interfaces have one of the following Interface Types:
    • Loopback
    • OSA-Express Queued Direct I/O (QDIO) Ethernet
    • HiperSockets
    • Multipath Channel Point-To-Point (MPCPTP)

The following views provide information in this workspace:

  • TCP Session Count: Shows a historical view of the number of active TCP sessions for the specified time period in a line graph.
  • Fragmentation and Reassembly: Shows a historical view of the packet fragmentation and reassembly operation for the specified time period in a time-line chart where:
    • Yellow represents the reassembly percentage.
    • Blue represents reassembly failure percentage.
    • Pink represents the fragmentation percentage.
    A high fragmentation or reassembly rate indicates that an adjacent device, such as a router, may have a too small window size.
  • TCP Connections Accepted: Shows a historical view of TCP connections accepted by the stack layer and the connections accepted high-water mark for the specified time period in a time-line chart, where:
    • Yellow represents the TCP connections accepted.
    • Blue represents the TCP connections accepted high-water mark.
  • TCP Connections Dropped: Shows a historical view of TCP connections dropped during the specified time period in a time-line chart.
  • UDP Datagram Rate: Compares the number of input and output datagrams for this TCP/IP stack layer over the specified time period in a time-line chart, where:
    • Blue represents the UDP receive datagram rate.
    • Green represents the UDP transmit datagram rate.
  • TCP/IP Stack Layers Summary History table: Provides detailed performance information about the TCP/IP stack layers displayed in the charts on the TCP/IP Stack Layers workspace.