Skip navigation

Discards

Why is the IfInDiscards counter incrementing?

Answer: There are several valid reasons that will cause the IfInDiscards counter to be incremented.

  1. If there are frames coming into a network port and that network port is not logically connected via connect, xbconnect, mapping, xbmapping or pass-all command, the IfInDiscards counter will increment for every frame seen on that port.
  2. If the destination tool port link status is down, frames destined for that tool port will be discarded at the network port interfaces for local connect, mapping and pass-all commands.
  3. When the network port is on GigaVUE Box 1 and the tool port is on GigaVUE Box 2, if the destination tool port link status is down, frames destined for that tool port will be discarded at the Box 2 stacking port interfaces for xbconnect and xbmapping commands.
  4. If an ‘allow’ type port-filter or xbport-filter is applied to a port, all frames that do not meet the filter criteria will be discarded.
  5. If a ‘deny’ type port-filter or xbport-filter is applied to a port, all frames that do meet the filter criteria will be discarded.
  6. If a network port is part of a map or xbmap, all frames that do not match any of the map-rules will be discarded at the network port.
  7. All error frames received at a network port will be discarded.
  8. All pause frames received at a network port will be discarded.
  9. All frames that come into a tool port interface will be discarded.
  10. GigaVUE-MP only: If a tool port is oversubscribed due to aggregating multiple network ports in a pass-all command, the IfInDiscards counter on the tool port will increment. This can be verified by enabling the Drop Packets SNMP Trap functionality in the GigaVUE-MP.
  11. GigaVUE-420 only: If a tool port is oversubscribed due to aggregating multiple network ports in any type of command, the IfInDiscards counter on the tool port will increment. This can be verified either by enabling the Drop Packets SNMP Trap functionality or examining the syslog.log file on the GigaVUE-420 system.

For Technical Support contact Gigamon Systems via email at support@gigamon.com or call 408-263-2024.