KB91425
Published: April 14, 2026
Revision: 1.0

Multiple UDP connection attempts with invalid connect strings may reset SNAP PAC controller


Applies To:

Firmware for:

  • SNAP-PAC-S1, SNAP-PAC-S1-FM, SNAP-PAC-S1-W
  • SNAP-PAC-S2, SNAP-PAC-S2-W
  • SNAP-PAC-R1, SNAP-PAC-R1-FM, SNAP-PAC-R1-W, SNAP-PAC-R1-B
  • SNAP-PAC-R2, SNAP-PAC-R2-FM, SNAP-PAC-R2-W
  • SoftPAC

Versions Affected:

R9.0a to current


Symptoms:

If a strategy uses the Open Outgoing Communication command multiple times with improperly formatted UDP connect strings, the affected controller may reset.

Workaround:

Verify the UDP connection strings are properly formatted. See the PAC Control User’s Guide (form 1700) for more information.

Resolution:

Opto 22 is investigating this issue.

Questions?

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


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