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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