OpenNMS Delta-V

Delta-V is a microservice decomposition of OpenNMS Horizon, transforming the monolithic Java application into independently deployable Kafka-connected containers.

For the original OpenNMS Horizon project description, see OPENNMS.md.

Architectural Direction

Delta-V has removed Apache Karaf/OSGi from the runtime architecture. All 12 service daemons and Minion run as standalone Spring Boot 4 applications on a jlink custom JRE built from alpine:3.21, deployed as individually-sized Docker images via layered JAR deduplication.

Delta-V code lives in the org.deltav package namespace with org.deltav.core Maven groupIds. Horizon-derived entity classes (opennms-model-jakarta) remain at org.opennms since horizon JARs reference them by FQN. Horizon dependencies are pre-built in the delta-v-horizon repository and consumed as Maven artifacts from GitHub Packages.

Where we are: All 12 daemons + Minion migrated to Spring Boot 4. The legacy opennms-config and opennms-model modules are fully decoupled from the daemon stack — all XML config loading uses Jackson XmlMapper with defaultUseWrapper(false). Layered JAR deduplication extracts shared dependencies (~80% overlap) into a common daemon-base Docker image (~415MB), with per-daemon overlay images adding only unique libraries. Each daemon starts in 2-4 seconds. 98 E2E tests pass across 8 test suites.

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Service Daemon Status

Deleted (12 daemons)

Daemon	Reason
Scriptd	Event-driven BSF scripting — unused, eliminated
Notifd	Notification system eliminated — alerts handled externally
Ackd	Acknowledgment daemon — unused
Actiond	Legacy shell-command execution on events
Vacuumd	Database maintenance automations — replaced by PostgreSQL native
Statsd	Unused statistics reporting
Tl1d	Legacy TL1 telecom protocol support
Queued	RRD write optimization — no longer needed
RTCd	Real-Time Console — dead without webapp
Ticketer	Trouble ticketing integration — not in microservice architecture
DHCPd	DHCP monitor/detector service

Migrated to Spring Boot 4 (12 daemons + Minion — complete)

Daemon	Spring Boot Module	Startup	Key Feature
Alarmd	daemon-boot-alarmd	2.7s	Full JPA (Hibernate 7)
EventTranslator	daemon-boot-eventtranslator	2.4s	JDBC-only, event-conf enrichment
Trapd	daemon-boot-trapd	2.0s	Kafka Sink bridge pattern (daemon-sink-kafka)
Syslogd	daemon-boot-syslogd	2.2s	Reuses Sink bridge, local DNS resolver
Discovery	daemon-boot-discovery	~2s	Kafka RPC client pattern (KafkaRpcClientConfiguration)
Provisiond	daemon-boot-provisiond	4.2s	JPA + 3x Kafka RPC + Quartz + SNMP adapters
BSMd	daemon-boot-bsmd	3.3s	JPA + AlarmLifecycleListener + REST API
Pollerd	daemon-boot-pollerd	4.1s	JPA + Kafka RPC + Twin API + PassiveStatusKeeper
PerspectivePollerd	daemon-boot-perspectivepollerd	3.6s	JPA + Kafka RPC + perspective outages + event self-consumption
Telemetryd	daemon-boot-telemetryd	3s	Pure ingestion bridge, multi-bridge KafkaSink, Twin API for OpenConfig
Enlinkd	daemon-boot-enlinkd	3.5s	JPA + Kafka RPC + LLDP/CDP/OSPF/ISIS/Bridge topology
Collectd	daemon-boot-collectd	~3s	JPA + Kafka RPC + SNMP collection + thresholding
Minion	daemon-boot-minion	~4s	Kafka RPC server + Kafka Sink + Twin API subscriber

Docker Images

Image	Base	Contents
opennms/jre-deltav:21	alpine:3.21	jlink custom JRE (22 modules) + diagnostic tools
opennms/daemon-base	jre-deltav:21	Shared libraries (~321 JARs deduped across 12 daemons)
opennms/<daemon>	daemon-base	Per-daemon unique libs + thin app JAR (12 images)
opennms/minion-boot	jre-deltav:21	Spring Boot 4 Minion — Kafka RPC server + Sink listeners + Twin API
opennms/db-init	jre-deltav:21	One-shot Liquibase schema migration

Shared Infrastructure

Module	Package	Purpose
daemon-common	org.deltav.core.daemon.common	DataSource, Kafka event transport, Kafka RPC client, AbstractDaoJpa, EventIpcManagerEnrichingWrapper
daemon-boot-minion-common	org.deltav.minion.common	Minion shared infra: KafkaTwinSubscriberConfiguration, PassiveStatusTwinSubscriber, SnmpV3 config sync
daemon-sink-kafka	org.deltav.core.daemon.sink.kafka	KafkaSinkBridge — consumes from Minion Sink topics (OpenNMS.Sink.*)
dao-jpa-support	org.deltav.core.daemon.common	AbstractDaoJpa base class + UpsertTemplate for JPA DAOs
event-forwarder-kafka	org.deltav.core.event.forwarder.kafka	KafkaEventForwarder + EventConfEnrichmentService
opennms-model-jakarta	org.opennms.netmgt.model	Jakarta Persistence entities + JPA DAOs + Enlinkd DAOs + utility classes (stays org.opennms)

Other Components Removed

Component	Reason
opennms-webapp	Legacy JSP webapp — removed from Maven reactor
opennms-webapp-rest	REST API for dead webapp
opennms-full-assembly	Monolithic assembly that packaged the webapp
Notification system	Tables, entities, DAOs, REST, Vaadin UI, config managers
OnmsEvent entity	Denormalized into OnmsAlarm/OnmsOutage; EventDao deleted
Database Reports	Jasper Reports, Availability Reports
Device Config Backup	Entire feature
Charts	Legacy JFreeChart bar charts
Self-monitoring	Deprecated monitors for monitoring OpenNMS itself
Eventd TCP/UDP listeners	Events arrive via Kafka only
MessageBus JMS	JMS implementation removed; Kafka-only
Zenith Connect	Cloud registration feature
RPM/Debian packaging	Native OS packages — Docker-only deployment

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What Is Delta-V?

OpenNMS Horizon is an enterprise-grade open-source network monitoring platform. Delta-V restructures it from a single 35.6 GB monolith into lean, focused microservices:

• Each daemon runs in its own container — independent scaling, isolation, and restartability
• Kafka-only event transport — no ActiveMQ, no shared event bus
• Events never touch PostgreSQL — only alarms are persisted to the database
• Layered Docker images — shared daemon-base (~415MB) + 12 per-daemon overlay images on a 143MB jlink Alpine JRE
• Spring Boot 4 migration complete — all 12 daemons + Minion run as JARs (2-4s startup); Karaf fully retired
• One-shot database initialization — opennms/db-init replaces the Core container for schema setup
• org.deltav package namespace — original delta-v code uses org.deltav.* packages; horizon-derived model-jakarta stays org.opennms

Architecture

Minion → Kafka Sink → Trapd/Syslogd
                          ↓
            KafkaEventForwarder → opennms-fault-events (Kafka)
                                        ↓
                        ┌───────────────┼───────────────┐
                        ↓               ↓               ↓
                    Alarmd      EventTranslator    All Daemons
                   (→ PostgreSQL)  (→ translate     (subscribe to
                                    → re-publish)   relevant events)
                                        ↓
                              opennms-ipc-events (Kafka)
                                        ↓
                              Provisiond, Discovery, etc.

Services

Service	Runtime	Purpose
alarmd	Spring Boot 4	Kafka → alarm creation/reduction → PostgreSQL
pollerd	Spring Boot 4	Service availability polling
collectd	Spring Boot 4	Performance data collection
perspectivepollerd	Spring Boot 4	Perspective (remote location) polling
discovery	Spring Boot 4	Network discovery (via Minion Kafka RPC)
trapd	Spring Boot 4	SNMP trap reception (via Minion Kafka Sink)
syslogd	Spring Boot 4	Syslog reception (via Minion Kafka Sink)
eventtranslator	Spring Boot 4	Event translation rules + enrichment
enlinkd	Spring Boot 4	Enhanced link discovery (LLDP/CDP/OSPF/ISIS/Bridge)
provisiond	Spring Boot 4	Node provisioning and scanning (via Minion Kafka RPC)
bsmd	Spring Boot 4	Business service monitoring
telemetryd	Spring Boot 4	Telemetry/flow ingestion bridge (via Minion Kafka Sink)
minion	Spring Boot 4	Distributed data collection agent (Kafka RPC + Sink + Twin API)
db-init	Spring Boot 4	One-shot Liquibase schema migration
postgres	postgres:15	PostgreSQL database (alarms only)
kafka	Apache Kafka	Event transport backbone

Kafka Topics

Topic	Purpose
opennms-fault-events	Alarm-bearing events (traps, syslog, translated events with alarm-data)
opennms-ipc-events	Daemon-to-daemon internal events (newSuspect, nodeScanCompleted, reloadDaemonConfig)
OpenNMS.Sink.Trap	Minion → Trapd raw trap forwarding
OpenNMS.Sink.Syslog	Minion → Syslogd raw syslog forwarding
OpenNMS.Sink.Telemetry-*	Minion → Telemetryd per-protocol flow forwarding
OpenNMS.twin.response	Pollerd → Minion Twin API state sync (passive status, SNMPv3 users)
OpenNMS.twin.request	Minion → Pollerd Twin API subscription requests

Quick Start

cd opennms-container/delta-v

# Start all 16 services
./deploy.sh up full

# Check service health
./deploy.sh status

# Run E2E tests
./test-e2e.sh              # Core: trap → provision → alarm lifecycle
./test-minion-e2e.sh       # Minion: trap → Kafka Sink → alarm lifecycle
./test-minion-rpc-e2e.sh   # Minion RPC: provision → detect → poll
./test-syslog-e2e.sh       # Syslog: Cisco syslog → alarm lifecycle
./test-passive-e2e.sh      # Passive: syslog → EventTranslator → Twin API → outage
./test-collectd-e2e.sh     # Collectd: SNMP collection health
./test-perspective-e2e.sh  # Perspective: remote-location polling + outage lifecycle
./test-enlinkd-e2e.sh      # Enlinkd: LLDP topology via Containerlab cEOS

Prerequisites

• JDK 21 (daemon/minion build and runtime)
• Docker Desktop with 16 GB memory (16 containers in full profile)
• snmptrap (net-snmp) for E2E tests

Building

See BUILD.md for detailed build instructions.

cd opennms-container/delta-v

# Full build: compile → JRE image → layered daemon images
./build.sh

# Or individual steps:
./build.sh compile    # Maven compile (22 modules, ~16s incremental)
./build.sh jre        # Build jlink custom JRE base image (rarely needed)
./build.sh deltav     # Build Delta-V layered images (daemon-base + 12 per-daemon + minion-boot)

Key Design Decisions

1. No events table — Events flow exclusively via Kafka. Only alarms are persisted to PostgreSQL by Alarmd.

2. No ActiveMQ — All cross-container communication uses Kafka topics.

3. Each daemon is self-contained — Every daemon container has its own EventWriter, EventListener, EventExpander, and KafkaEventForwarder.

4. Producer-side event enrichment — Each daemon's KafkaEventForwarder loads event definitions from the database via EventConfEnrichmentService and applies severity + alarm-data before publishing to Kafka.

5. Minion communicates via Kafka only — No REST dependency. SNMPv3 user config distributed via Twin API.

6. Minion is sole network ingress — No daemon container binds external UDP/TCP monitoring ports. All protocol data enters via Minion → Kafka Sink → KafkaSinkBridge. All polling/collection executes on Minion via Kafka RPC (force-remote=true).

7. Twin API state sync — Bidirectional config/state sync between daemons and Minion via Kafka Twin topics.

8. Jackson XmlMapper for config — All daemon-boot modules use Jackson XmlMapper with defaultUseWrapper(false) and JaxbAnnotationModule. Legacy JaxbUtils/JAXB eliminated.

9. org.deltav package namespace — All original delta-v code uses org.deltav.* packages with BeaconStrategists copyright. Horizon-derived code (model-jakarta, BSM entities) stays org.opennms with dual copyright attribution.

10. Horizon as pre-built dependency — Horizon modules are built in pbrane/delta-v-horizon and consumed as Maven artifacts, keeping delta-v's 22-module reactor fast (~16s compile).

Documentation

Document	Description
OPENNMS.md	Original OpenNMS Horizon project description
BUILD.md	Build instructions
CLAUDE.md	AI assistant project context
SECURITY.md	Security policy
NOTICE	OpenNMS derivation attribution

Design documents are in docs/plans/ and docs/superpowers/.

License

This project is licensed under the GNU Affero General Public License v3.