apache/skywalking · error · RuntimeException

Illegal Service Instance Relation entity id

Error message

Illegal Service Instance Relation entity id

What it means

RuntimeException thrown by IDManager.ServiceInstanceID.analysisRelationId(String) when a service-instance relation entity id does not split into exactly 2 parts. Valid ids come from buildRelationId as instanceId + RELATION_ID_CONNECTOR + relatedInstanceId; anything with a different segment count is rejected. Note the parallel hierarchy builder (for instance layers) emits 4-segment ids that this method cannot parse.

Source

Thrown at oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/analysis/IDManager.java:178

        }

        /**
         * @return encoded instance hierarchy relation id
         */
        public static String buildInstanceHierarchyRelationId(InstanceHierarchyRelationDefine define) {
            return define.instanceId + Const.SERVICE_ID_CONNECTOR + define.serviceLayer.value() +
                Const.RELATION_ID_CONNECTOR +
                define.relatedInstanceId + Const.SERVICE_ID_CONNECTOR + define.relatedServiceLayer.value();
        }

        /**
         * @return service instance relation ID object decoded from {@link #buildRelationId(ServiceInstanceRelationDefine)}
         * result
         */
        public static ServiceInstanceID.ServiceInstanceRelationDefine analysisRelationId(String entityId) {
            String[] parts = entityId.split(Const.RELATION_ID_PARSER_SPLIT);
            if (parts.length != 2) {
                throw new RuntimeException("Illegal Service Instance Relation entity id");
            }
            return new ServiceInstanceID.ServiceInstanceRelationDefine(parts[0], parts[1]);
        }

        @RequiredArgsConstructor
        @Getter
        public static class InstanceIDDefinition {
            /**
             * Built by {@link ServiceID#buildId(String, boolean)}
             */
            private final String serviceId;
            private final String name;
        }

        @RequiredArgsConstructor
        @Getter
        @EqualsAndHashCode
        public static class ServiceInstanceRelationDefine {

View on GitHub (pinned to 102af09b4a)

Solutions

1. Use ServiceInstanceID.buildRelationId(...) to create ids and only decode its output with analysisRelationId
2. Choose a dedicated parser for 4-segment hierarchy ids rather than this method
3. Log the offending entityId (it is not in the message — add it at the call site or inspect the argument) and audit its producer
4. Add a defensive parts.length check before calling in integration code

Example fix

// before
String[] p = entityId.split("\\.");
IDManager.ServiceInstanceID.analysisRelationId(p[0] + "." + p[1]); // mangled id

// after
ServiceInstanceRelationDefine def =
    IDManager.ServiceInstanceID.analysisRelationId(entityId); // pass the id through untouched

if (entityId == null || entityId.split("\\.").length != 2) {
    throw new IllegalArgumentException("Not a plain instance-relation id (4 segments means hierarchy format): " + entityId);
}

boolean isPlainInstanceRelationId(String id) {
    return id != null && id.split("\\.").length == 2;
}

try {
    ServiceInstanceRelationDefine def = IDManager.ServiceInstanceID.analysisRelationId(entityId);
} catch (RuntimeException e) {
    LOGGER.warn("Dropping malformed instance relation id: {}", entityId, e);
}

When it happens

Trigger: Feeding a hierarchy-format instance relation id (instance + layer + connector + related instance + layer) into analysisRelationId; hand-built relation strings with wrong connector count; null or empty input; corrupted storage values.

Common situations: New code paths distinguishing layered vs plain instance relations picking the wrong parser; query/GraphQL layer code re-splitting ids manually then passing remnants downstream; data written by a divergent fork.

Related errors

• Can't split service id into 2 parts, {}
• Illegal Service Relation entity id
• Can't split instance id into 2 parts, {}
• Can't split endpoint id into 2 parts, {}
• Illegal endpoint Relation entity id, {}

AI-assisted analysis of apache/skywalking@102af09b4a (2026-08-14). Data as JSON: /api/errors/5be20a2b8c6773af. Report an issue: GitHub.