LogrobotLM

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FANUC Alarm HOST-187 — WARN NETMEM: receive socket open fail

FANUC HOST-187 (“WARN NETMEM: receive socket open fail”): UDP open for datagram receiving was failed. First check: Verify that there is RLSYNC entry in $SERVENT system variable.

Updated 2026-09-17 · LogrobotLM reference

Description

UDP open for datagram receiving was failed.

Remedy

Verify that there is RLSYNC entry in $SERVENT system variable. Verify that port number for RLSYNC is correct.

Related codes

HOST-185WARN NETMEM: receive BD errorHOST-186WARN NETMEM: send socket open failHOST-188WARN PPP init on port … failsHOST-189WARN Invalid port number

Indicative field information — the robot manufacturer's manual and safety procedures always prevail. Never bypass a safety device; apply lockout/tagout (LOTO) before any physical intervention. How this reference is built →