KB80041
Published: June 26, 2008
Revision: 2.0

Excessive I/O unit timeouts possible if communication bursts overwhelm Ethernet network


Applies To:

SNAP-PAC-S1
SNAP-PAC-S2
SNAP-PAC-R1
SNAP-PAC-R2
SNAP-PAC-EB1
SNAP-PAC-EB2

Versions Affected:

Problem was discovered in version: R8.1a
Problem is fixed in version: R8.2a

Resolved In Version:

Problem is fixed in version: R8.2a


Symptoms:

Excessive Ethernet I/O device timeouts (-9) may occur as a result of packet loss when incoming packet bursts overwhelm network resources available on a receiving device (such as a control engine). Factors that can cause excessive bursts in communication include:

  • Communication from many Ethernet I/O units responding back at the same time.
  • Many PAC Control strategy charts are currently running and they generate Ethernet activity that cause the host port to be bombarded with responses.
  • Broadcast and multicast messages that may overwhelm the Ethernet network.

    • Resolution:

      Opto 22 has resolved this issue.


      Questions?

      Contact: Opto 22 Product Support.
      Phone: 800-835-6786 or 951-695-3080
      Email: support@opto22.com


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