add switch for dropping dns records

.gitignore

@@ -1 +1,2 @@
-maintain/
+maintain/
+project*

README.md

@@ -1,34 +1,101 @@
-# Alpine :: Traefik Labels
-![size](https://img.shields.io/docker/image-size/11notes/traefik-labels/latest?color=0eb305) ![version](https://img.shields.io/docker/v/11notes/traefik-labels?color=eb7a09) ![pulls](https://img.shields.io/docker/pulls/11notes/traefik-labels?color=2b75d6) ![activity](https://img.shields.io/github/commit-activity/m/11notes/docker-traefik-labels?color=c91cb8) ![commit-last](https://img.shields.io/github/last-commit/11notes/docker-traefik-labels?color=c91cb8)
+![Banner](https://github.com/11notes/defaults/blob/main/static/img/banner.png?raw=true)
 
-Run Traefik Labels based on Alpine Linux. Small, lightweight, secure and fast 🏔️
+# 🏔️ Alpine - Traefik Labels
+![size](https://img.shields.io/docker/image-size/11notes/traefik-labels/0.3.0?color=0eb305) ![version](https://img.shields.io/docker/v/11notes/traefik-labels/0.3.0?color=eb7a09) ![pulls](https://img.shields.io/docker/pulls/11notes/traefik-labels?color=2b75d6)
 
-What can I do with this? Simply put: It will export any traefik labels on a container on the same host as this image runs to a Redis instance. This makes it possible for a centralized Traefik load balancer to update endpoints dynamically by utilizing the docker labels, just like you would on a local installation of Traefik with labels. It is meant as an alternative and simple way to proxy requests from a Traefik load balanacer to multiple docker nodes running in different networks and locations.
+**Export Traefik labels from any Docker node to a central location**
 
-In order to use this image, you need to setup Traefik with a Redis provider and then point this image via REDIS_URL to the same Redis instance. Each entry will have an expire timer set in Redis, so that if a container is removed by a server crashing, Redis will automatically remove stale entries as well. Entries are refreshed every 300 seconds or on all docker container events (create, run, kill, stop, restart, ...).
+# SYNOPSIS
+What can I do with this? This image will connect to all your Docker nodes and read their labels. It will then use the labels to update your Traefik configuration in Redis automatically and dynamically on each container start, stop or timeout. It also supports updating your internal and external DNS servers too, so you can use labels for everything. If a container is removed the image will automatically reverse any `nsupdate update add` to `nsupdate update delete` so entries are removed too.
 
-This image provides the ability to call a webhook for each container for each event or poll after the data was updates in Redis.
+In order to use this image, you need to setup Traefik with a Redis provider and then point this image via redis.url to the same Redis instance. Each entry will have an expire timer set in Redis, so that if a container is removed by a server crashing, Redis will automatically remove stale entries as well. Entries are refreshed every 300 seconds or on all docker container events (create, run, kill, stop, restart, ...). As for nsupdate, you need to setup tsig authentication in your NS servers and add the keys to the zones you want to be able to update, you can restrict the keys by using update-policy if you use Bind from ISC.
 
-## Run
-```shell
-docker run --name traefik-labels \
-  -v /run/docker.sock:/run/docker.sock \
-  -e LABELS_REDIS_URL="rediss://foo:bar@10.127.198.254:6379/0" \
-  -d 11notes/traefik-labels:[tag]
+This image provides the ability to call a webhook for each container for each event or poll after the data was updates in Redis and or nsupdate.
+
+Each node gets its own worker thread for better scalability. If you have 10 nodes, you will have 10 worker processes inside the container forked from the main process. Forks die when their node disconnects and use the `ping.interval` to fork new processes indefinitely. As soon as the node is back online, it will always execute a poll on all containers of that node.
+
+# VOLUMES
+* **/labels/etc** - Directory of config.yaml
+* **/labels/ssl** - Directory of ssl certificates for TLS<sup>1</sup>
+
+# COMPOSE
+```yaml
+name: "traefik-labels"
+services:
+  redis:
+    image: "11notes/redis:7.2.5"
+    container_name: "redis"
+    environment:
+      REDIS_PASSWORD: "**************"
+      TZ: Europe/Zurich
+    volumes:
+      - "redis.etc:/redis/etc"
+      - "redis.var:/redis/var"
+    networks:
+      - redis
+    restart: always
+  labels:
+    image: "11notes/traefik-labels:0.3.0"
+    container_name: "labels"
+    environment:
+      TZ: Europe/Zurich
+    volumes:
+      - "labels.etc:/labels/etc"
+    networks:
+      - redis
+      - nodes
+    restart: always
+volumes:
+  redis.etc:
+  redis.var:
+  labels:etc:
+networks:
+  redis:
+    internal: true
+  nodes:
 ```
 
-```shell
-docker run --name traefik-labels \
-  -v /run/docker.sock:/run/docker.sock \
-  -e LABELS_REDIS_URL="rediss://foo:bar@10.127.198.254:6379/0" \
-  -e LABELS_WEBHOOK="https://domain.com/traefik/labels" \
-  -e LABELS_WEBHOOK_AUTH_BASIC="foo:bar" \
-  -d 11notes/traefik-labels:[tag]
+# EXAMPLES
+## config /labels/etc/config.yaml
+```yaml
+labels:
+  redis:
+    url: rediss://foo:bar@10.127.198.254:6379/0
+  webhook:
+    url: https://my.cool.webhook/v1
+    # optional
+    auth:
+      # supports basic authentication
+      basic: labels:*****
+  nodes:
+    # use FQDN and add the FQDN to your certificates SAN list (or IP)
+    - 192.168.18.12
+    - 10.14.120.1
+  # reload labels.nodes every {n} seconds (0 = disabled)
+  interval: 0
+  # timeout in seconds for the connection to a Docker node
+  timeout: 2.5
+  rfc2136:
+    # only nsupdate on entries which are different (do not update same data)
+    verify: false
+    # remove DNS entry if container is unreachable
+    remove: false
+  poll:
+    # polling all containers on a node every {n} seconds
+    interval: 300
+  ping:
+    # ping all nodes every {n} seconds to see if they are still online
+    interval: 10
+  tls:
+    # path for TLS certificates
+    ca: /labels/ssl/ca.crt
+    crt: /labels/ssl/server.crt
+    key: /labels/ssl/server.key
 ```
 
-This is a demo webserver that will start on :8080, all the traefik labels will be exportet to the Redis instance. They follow the exact same [syntax](https://doc.traefik.io/traefik/routing/providers/kv/) as for normal Redis and Traefik, just as labels.
+## container on a node with Traefik routes
 ```shell
-docker run --name demo \
+docker run --name traefik-demo \
   -p 8080:8080 \
   -l "traefik/http/routers/demo.domain.com/service=demo.domain.com" \
   -l "traefik/http/routers/demo.domain.com/rule=Host(`demo.domain.com`)" \
@@ -38,33 +105,72 @@ docker run --name demo \
   -d 11notes/nginx:stable
 ```
 
-## Defaults
+## container on a node with Traefik routes and rfc2136 DNS
+```shell
+docker run --name traefik-rfc2136-demo \
+  -p 8080:8080 \
+  -l "traefik/http/routers/demo.domain.com/service=demo.domain.com" \
+  -l "traefik/http/routers/demo.domain.com/rule=Host(`demo.domain.com`)" \
+  -l "traefik/http/routers/demo.domain.com/tls=true" \
+  -l "traefik/http/routers/demo.domain.com/entrypoints=https" \
+  -l "traefik/http/services/demo.domain.com/loadbalancer/servers/0/url=http://fqdn-of-docker-node:8080" \
+  -l "rfc2136/WAN/server=ns.domain.com" \
+  -l "rfc2136/WAN/key=algo:name:secret" \
+  -l "rfc2136/WAN/nsupdate=update add foo.domain.com 300 A 175.12.41.11" \
+  -l "rfc2136/WAN/nsupdate=update add foo.domain.com 300 TXT \"hello from traefik-labels!\"" \
+  -l "rfc2136/LAN/server=ns.domain.local" \
+  -l "rfc2136/LAN/key=algo:name:secret" \
+  -l "rfc2136/LAN/nsupdate=update add foo.domain.local 300 A 192.168.12.54" \
+  -d 11notes/nginx:stable
+```
+
+# DEFAULT SETTINGS
 | Parameter | Value | Description |
 | --- | --- | --- |
 | `user` | docker | user docker |
 | `uid` | 1000 | user id 1000 |
 | `gid` | 1000 | group id 1000 |
 | `home` | /labels | home directory of user docker |
+| `config` | /labels/etc/config.yaml | config (nodes can be updated dynamically) |
+| `ca.crt` | /labels/ssl/ca.crt | Certificate of CA for TLS<sup>1</sup> |
+| `labels.crt` | /labels/ssl/labels.crt | Certificate of client for TLS<sup>1</sup> |
+| `labels.key` | /labels/ssl/labels.key | Private key of client for TLS<sup>1</sup> |
 
-## Environment
+# ENVIRONMENT
 | Parameter | Value | Default |
 | --- | --- | --- |
-| `LABELS_REDIS_URL` | the redis URL to connect, use rediss:// for SSL | rediss://localhost:6379/0 |
-| `LABELS_INTERVAL` | in what interval container information is pulled in seconds | 300 |
-| `LABELS_TIMEOUT` | how many seconds after an interval the keys should stay till they expire in seconds | 30 |
-| `LABELS_WEBHOOK` | URL to call on each event or poll for each container |  |
-| `LABELS_WEBHOOK_AUTH_BASIC` | Basic authentication to use in the form of "username:password" for the webhook |  |
+| `TZ` | [Time Zone](https://en.wikipedia.org/wiki/List_of_tz_database_time_zones) | |
+| `DEBUG` | Show debug information | |
 
-## Parent image
-* [11notes/node:stable](https://github.com/11notes/docker-node)
+# SOURCE
+* [11notes/traefik-labels:0.3.0](https://github.com/11notes/docker-traefik-labels/tree/0.3.0)
 
-## Built with and thanks to
+# PARENT IMAGE
+* [11notes/node:stable](https://hub.docker.com/r/11notes/node)
+
+# BUILT WITH
 * [npm::redis](https://www.npmjs.com/package/redis)
 * [npm::dockerode](https://www.npmjs.com/package/dockerode)
 * [nodejs](https://nodejs.org/en)
-* [Alpine Linux](https://alpinelinux.org)
+* [alpine](https://alpinelinux.org)
 
-## Tips
-* Only use rootless container runtime (podman, rootless docker)
-* Don't bind to ports < 1024 (requires root), use NAT/reverse proxy (haproxy, traefik, nginx)
-* Do not access docker.sock as root
+# TIPS
+* Use a reverse proxy like Traefik, Nginx to terminate TLS with a valid certificate
+* Use Let’s Encrypt certificates to protect your SSL endpoints
+
+# DISCLAIMERS
+* <sup>1</sup> For TLS to work you need proper certificates in place for your dockerd and your clients. The CN in the certificate needs to match the FQDN or IP you have set on the docker node, you can set multiple by using SAN. See an example of a daemon.json configuration to enable TLS.
+```json
+{
+  "tls": true,
+  "tlsverify": true,
+  "tlscacert": "/etc/docker/ca.crt",
+  "tlscert": "/etc/docker/server.crt",
+  "tlskey": "/etc/docker/server.key",
+  "hosts": ["unix:///var/run/docker.sock", "tcp://0.0.0.0:2376"]
+}
+```
+
+# ElevenNotes<sup>™️</sup>
+This image is provided to you at your own risk. Always make backups before updating an image to a new version. Check the changelog for breaking changes. You can find all my repositories on [github](https://github.com/11notes).
+    

amd64.dockerfile

@@ -1,3 +1,11 @@
+# :: Util
+  FROM alpine as util
+
+  RUN set -ex; \
+    apk add --no-cache \
+      git; \
+    git clone https://github.com/11notes/util.git;
+
 # :: Header
   FROM 11notes/node:stable
   ENV APP_ROOT=/labels
@@ -7,13 +15,19 @@
 
   # :: prepare image
     RUN set -ex; \
-      mkdir -p ${APP_ROOT};
+      mkdir -p ${APP_ROOT}/lib; \
+      apk --no-cache add \
+        bind-tools; \
+      apk --no-cache upgrade;
+
+    COPY --from=util /util/node/util.js /labels/lib
 
   # :: install
     RUN set -ex; \
       cd ${APP_ROOT}; \
       npm --save install \
         redis@4.6.11 \
+        js-yaml@4.1.0 \
         dockerode@4.0.0;
 
   # :: update image

arm64v8.dockerfile

@@ -1,11 +1,17 @@
-# :: Builder
-  FROM alpine AS qemu
-  ENV QEMU_URL https://github.com/balena-io/qemu/releases/download/v3.0.0%2Bresin/qemu-3.0.0+resin-aarch64.tar.gz
-  RUN apk add curl && curl -L ${QEMU_URL} | tar zxvf - -C . && mv qemu-3.0.0+resin-aarch64/qemu-aarch64-static .
+# :: Util
+  FROM alpine as util
+
+  RUN set -ex; \
+    apk add --no-cache \
+      git; \
+    git clone https://github.com/11notes/util.git;
+
+# :: QEMU
+  FROM multiarch/qemu-user-static:x86_64-aarch64 as qemu
 
 # :: Header
-  FROM arm64v8/node:20.10.0-alpine3.19
-  COPY --from=qemu qemu-aarch64-static /usr/bin
+  FROM --platform=linux/arm64 11notes/node:stable
+  COPY --from=qemu /usr/bin/qemu-aarch64-static /usr/bin
   ENV APP_ROOT=/labels
 
 # :: Run
@@ -13,13 +19,19 @@
 
   # :: prepare image
     RUN set -ex; \
-      mkdir -p ${APP_ROOT};
+      mkdir -p ${APP_ROOT}/lib; \
+      apk --no-cache add \
+        bind-tools; \
+      apk --no-cache upgrade;
+
+    COPY --from=util /util/node/util.js /labels/lib
 
   # :: install
     RUN set -ex; \
       cd ${APP_ROOT}; \
       npm --save install \
         redis@4.6.11 \
+        js-yaml@4.1.0 \
         dockerode@4.0.0;
 
   # :: update image

compose.yaml

@@ -0,0 +1,33 @@
+name: "traefik-labels"
+services:
+  redis:
+    image: "11notes/redis:7.2.5"
+    container_name: "redis"
+    environment:
+      REDIS_PASSWORD: "**************"
+      TZ: Europe/Zurich
+    volumes:
+      - "redis.etc:/redis/etc"
+      - "redis.var:/redis/var"
+    networks:
+      - redis
+    restart: always
+  labels:
+    image: "11notes/traefik-labels:0.3.0"
+    container_name: "labels"
+    environment:
+      TZ: Europe/Zurich
+    volumes:
+      - "labels.etc:/labels/etc"
+    networks:
+      - redis
+      - nodes
+    restart: always
+volumes:
+  redis.etc:
+  redis.var:
+  labels:etc:
+networks:
+  redis:
+    internal: true
+  nodes:

multi-arch-manifest-latest.yaml

@@ -0,0 +1,11 @@
+image: 11notes/traefik-labels:latest
+manifests:
+  - image: 11notes/traefik-labels:amd64-latest
+    platform:
+      architecture: amd64
+      os: linux
+  - image: 11notes/traefik-labels:arm64v8-latest
+    platform:
+      architecture: arm64
+      os: linux
+      variant: v8

multi-arch-manifest-version.yaml

@@ -0,0 +1,11 @@
+image: 11notes/traefik-labels:0.3.0"
+manifests:
+  - image: 11notes/traefik-labels:0.3.0"
+    platform:
+      architecture: amd64
+      os: linux
+  - image: 11notes/traefik-labels:0.3.0"
+    platform:
+      architecture: arm64
+      os: linux
+      variant: v8

rootfs/labels/dig.js

@@ -0,0 +1,27 @@
+const { spawn } = require('node:child_process');
+const { elevenLogJSON } = require('/labels/lib/util.js');
+
+exports.dig = async(resolver, type, record) => {
+  return(new Promise((resolve, reject) => {
+    const dig = spawn('/usr/bin/dig', ['+short', '+answer', type, record, `@${resolver}`]);
+    const io = {stdout:'', stderr:''};
+    dig.stderr.on('data', data => {io.stderr += data.toString()});
+    dig.stdout.on('data', data => {io.stdout += (data.toString()).replace(/[\r\n]*$/ig, '')});
+    dig.on('error', error => {reject(error)});
+    dig.on('close', code =>{
+      elevenLogJSON('debug', {method:'dig()', params:{resolver:resolver, type:type, record:record}, io:io});
+      switch(true){
+        case /no servers could be reached/ig.test(io.stdout): io.stderr += io.stdout; break;
+      }
+      if(code === 0){
+        if(io.stderr.length > 0){
+          reject(io.stderr);
+        }else{
+          resolve(io.stdout);
+        }
+      }else{
+        reject(io.stderr);
+      }
+    });
+  }));
+}

rootfs/labels/etc/config.yaml

@@ -0,0 +1,33 @@
+labels:
+  redis:
+    url: rediss://foo:bar@10.127.198.254:6379/0
+  webhook:
+    url: https://my.cool.webhook/v1
+    # optional
+    auth:
+      # supports basic authentication
+      basic: labels:*****
+  nodes:
+    # use FQDN and add the FQDN to your certificates SAN list (or IP)
+    - 192.168.18.12
+    - 10.14.120.1
+  # reload labels.nodes every {n} seconds (0 = disabled)
+  interval: 0
+  # timeout in seconds for the connection to a Docker node
+  timeout: 2.5
+  rfc2136:
+    # only nsupdate on entries which are different (do not update same data)
+    verify: false
+    # remove DNS entry if container is unreachable
+    remove: false
+  poll:
+    # polling all containers on a node every {n} seconds
+    interval: 300
+  ping:
+    # ping all nodes every {n} seconds to see if they are still online
+    interval: 10
+  tls:
+    # path for TLS certificates
+    ca: /labels/ssl/ca.crt
+    crt: /labels/ssl/server.crt
+    key: /labels/ssl/server.key

rootfs/labels/main.js

@@ -1,144 +1,276 @@
-process.once('SIGTERM', () => process.exit(0));
-process.once('SIGINT', () => process.exit(0));
-
-const Docker = require('dockerode');
+const { fork } = require('node:child_process');
+const fs = require('fs');
+const yaml = require('js-yaml');
 const redis = require('redis');
+const { nsupdate } = require('./nsupdate');
+const { dig } = require('./dig');
+const { elevenLogJSON } = require('/labels/lib/util.js');
+
+process
+  .on('unhandledRejection', (e, p) => {
+    elevenLogJSON('error', {unhandledRejection:e.toString()});
+  })
+  .on('uncaughtException', e => {
+    elevenLogJSON('error', {uncaughtException:e.toString()});
+  });
 
-const ERROR = 1;
-const POLL_INTERVAL = parseInt(process.env?.LABELS_INTERVAL || 300);
-const POLL_TIMEOUT = parseInt(process.env?.LABELS_TIMEOUT|| 30);
 
 class Labels{
-  #docker;
+  #config = {webhook:{headers:{'Content-Type':'application/json'}}};
+  #workers = {};
+  #interval = {run:false, fok:false};
   #redis;
-  #poll = false;
-  #webhook = {
-    headers:{'Content-Type':'application/json'}
-  };
 
   constructor(){
-    this.#docker = new Docker({socketPath:'/run/docker.sock'});
-    if(undefined !== process.env.LABELS_WEBHOOK_AUTH_BASIC){
-      this.#webhook.headers['Authorization'] = 'Basic ' + Buffer.from(process.env.LABELS_WEBHOOK_AUTH_BASIC).toString('base64')
+    const config = yaml.load(fs.readFileSync(`${process.env.APP_ROOT}/etc/config.yaml`, 'utf8'))?.labels;
+    this.#config.redis = {url:(config?.redis?.url || 'rediss://localhost:6379/0')};
+    this.#config.webhook.url = (config?.webhook?.url || null);
+    if(this.#config.webhook.url && config?.webhook?.auth?.basic){
+      this.#config.webhook.headers['Authorization'] = 'Basic ' + Buffer.from(config.webhook.auth.basic).toString('base64');
+      elevenLogJSON('info', `using webhook ${this.#config.webhook.url} with basic authentication`);
+    }
+    this.#config.rfc2136 = {verify:(config?.rfc2136?.verify || false), remove:(config?.rfc2136?.remove || false)};
+    this.#config.poll = {interval:(config?.poll?.interval || 300)};
+    this.#config.ping = {interval:(config?.ping?.interval || 2.5)};
+    this.#config.port = (config?.port || 2376);
+    this.#config.timeout = (config?.timeout || 5);
+    this.#config.interval = (config?.interval || 0);
+    this.#config.tls = {
+      ca:(config?.tls?.ca || `${process.env.APP_ROOT}/ssl/ca.crt`),
+      crt:(config?.tls?.crt || `${process.env.APP_ROOT}/ssl/labels.crt`),
+      key:(config?.tls?.key || `${process.env.APP_ROOT}/ssl/labels.key`),
+    };
+
+    if(this.#config.interval > 0){
+      elevenLogJSON('info', `${process.env.APP_ROOT}/etc/config.yaml will reload labels.nodes every ${this.#config.interval}s`);
     }
   }
 
-  #log(message, type){
-    console.log(JSON.stringify({
-      time:new Date().toISOString(),
-      type:(type === ERROR) ? 'ERROR' : 'INFO',
-      message:message,
-    }));
-  }
-
-  async watch(){
-    if(undefined !== process.env.LABELS_WEBHOOK){
-      this.#log(`using webhook ${process.env.LABELS_WEBHOOK}`);
-    }
-
+  async run(){
     this.#redis = await redis.createClient({
-      url:process.env.LABELS_REDIS_URL,
+      url:this.#config.redis.url,
       pingInterval:30000,
       socket:{
-        rejectUnauthorized: false,
-      }
+        rejectUnauthorized:false,
+      },
+      disableOfflineQueue:false,
+      commandsQueueMaxLength:1024
     });
 
-    this.#redis.connect();
-    this.#redis.on('ready', ()=>{
-      this.#log('successfully connected to redis');
-      (async() => {
-        await this.dockerPoll();
-      })();
-      this.dockerEvents();
+    this.#redis.on('ready', async()=>{
+      elevenLogJSON('info', `connected to redis`);
+
+      this.#run();
+
+      if(this.#config.interval > 0){
+        setInterval(async ()=>{
+          if(!this.#interval.run){
+            this.#interval.run = true;
+            try{
+              await this.#run();
+            }catch(e){
+              elevenLogJSON('error', {error:e});
+            }finally{
+              this.#interval.run = false;
+            }
+          }
+        }, this.#config.interval*1000);
+      }
+  
+      setInterval(async()=>{
+        if(!this.#interval.fork){
+          this.#interval.fork = true;
+          try{
+            await this.#fork();
+          }catch(e){
+            elevenLogJSON('error', {error:e});
+          }finally{
+            this.#interval.fork = false;
+          }
+        }
+      }, this.#config.ping.interval*1000);
     });
 
     this.#redis.on('error', error =>{
-      this.#log(error, ERROR);
+      elevenLogJSON('error', {redis:error.toString()});
     });
 
-    setInterval(async() => {
-      await this.dockerPoll();
-    }, POLL_INTERVAL*1000);
+    this.#redis.connect();
   }
 
-  dockerEvents(){
-    this.#docker.getEvents({}, (error, data) => {
-      if(error){
-        this.#log(error, ERROR);
-      }else{
-        data.on('data', async(chunk) => {
-          const event = JSON.parse(chunk.toString('utf8'));
-          if(/Container/i.test(event?.Type) && /^(start|kill)$/i.test(event?.status)){
-            await this.dockerInspect(event.id, event.status);
-          }
-        });
-      }
-    });
-  }
-
-  async dockerPoll(){
-    if(!this.#poll){
-      try{
-        this.#poll = true;
-        this.#docker.listContainers((error, containers) => {
-          if(!error){
-            containers.forEach(async(container) => {
-              await this.dockerInspect(container.Id, 'poll');
-            });
-          }
-        });
-      }catch(e){
-        this.#log(e, ERROR);
-      }finally{
-        this.#poll = false;
+  #run(){
+    const nodes = yaml.load(fs.readFileSync(`${process.env.APP_ROOT}/etc/config.yaml`, 'utf8'))?.labels?.nodes;
+    for(const node of nodes){
+      if(!this.#workers[node]){
+        this.#workers[node] = new Worker(this.#config, node, this);
+        this.#workers[node].fork();
+        elevenLogJSON('info', `created new worker for node [${node}]`);
       }
     }
   }
 
-  dockerInspect(id, status = null){
-    return(new Promise((resolve, reject) => {
-      const container = this.#docker.getContainer(id);
-      container.inspect(async(error, data) => {
-        if(!error){
-          const update = (/start|poll/i.test(status)) ? true : false;
-          const webHook = {event:status, labels:{}};
-          let log = false;
+  async #fork(){
+    for(const node in this.#workers){
+      if(!this.#workers[node].run){
+        await this.#workers[node].fork();
+        if(!this.#workers[node].log.disconnect){
+          this.#workers[node].log.disconnect = true;
+          elevenLogJSON('info', `trying to fork existing worker for node [${node}] after disconnect`);
+        }
+      }
+    }
+  }
+
+  async inspect(container){
+    try{
+      const counter = {
+        add:0,
+        del:0,
+      };
+      const rfc2136 = {
+        WAN:{server:'', key:'', commands:[]},
+        LAN:{server:'', key:'', commands:[]},
+      }
       
-          for(const label in data?.Config?.Labels){
-            if(/traefik\//i.test(label)){
-              if(!log){
-                this.#log(`inspect container {${(data?.Name || data?.id).replace(/^\//i, '')}}${(
-                  (null === status) ? '' : ` event[${status}]`
-                )} traefik labels`);
-                log = true;
-              }
-              if(undefined !== process.env.LABELS_WEBHOOK){
-                webHook.labels[label] = data?.Config?.Labels[label];
-              }
-              if(update){
-                await this.#redis.set(label, data?.Config?.Labels[label], {EX:POLL_INTERVAL + POLL_TIMEOUT});
-              }else{
-                await this.#redis.del(label);
-              }
+      for(const label in container.labels){
+        switch(true){
+          case /traefik\//i.test(label):
+            if(container.start){
+              counter.add++;
+              await this.#redis.set(label, container.labels[label], {EX:this.#config.poll.interval + 30});
+            }else{
+              counter.del++;
+              await this.#redis.del(label);
+            }
+          break;
+
+          case /rfc2136\//i.test(label):
+            const type = ((label.match(/rfc2136\/WAN\//i)) ? 'WAN' : 'LAN');
+            switch(true){
+              case /rfc2136\/\S+\/server/i.test(label):
+                rfc2136[type].server = container.labels[label];
+              break;
+
+              case /rfc2136\/\S+\/key/i.test(label):
+                rfc2136[type].key = container.labels[label];
+              break;
+
+              default:
+                if(!container.start && this.#config.rfc2136.remove){
+                  container.labels[label] = container.labels[label].replace(/update add/i, 'update delete');
+                }
+                rfc2136[type].commands.push(container.labels[label]);
+            }
+          break;
+        }
+      }
+
+      if(rfc2136.LAN.commands.length > 0 || rfc2136.WAN.commands.length){
+        await this.#rfc2136(rfc2136);
+      }
+
+      if(this.#config?.webhook?.url){
+        await this.#webhook(container);
+      }
+
+    }catch(e){
+      elevenLogJSON('error', {inspect:e.toString(), exception:e});
+    }
+  }
+
+  async #rfc2136(rfc2136){
+    for(const type in rfc2136){
+      if(rfc2136[type].commands.length > 0 && rfc2136[type].server && rfc2136[type].key){
+        if(this.#config.rfc2136.verify){
+          for(let i=0; i<rfc2136[type].commands.length; i++){
+            if(await this.#rfc2136knownRecord(rfc2136[type].server, rfc2136[type].commands[i])){
+              rfc2136[type].commands.splice(i, 1);
             }
           }
-
-          if(undefined !== process.env.LABELS_WEBHOOK){           
-            try{
-              await fetch(process.env.LABELS_WEBHOOK, {method:(
-                (update) ? 'PUT' : 'DELETE'
-              ), body:JSON.stringify(webHook), headers:this.#webhook.headers, signal:AbortSignal.timeout(2500)});
-            }catch(e){
-              this.#log(e, ERROR);
-            }
+        }
+        try{
+          if(rfc2136[type].commands.length > 0){
+            await nsupdate(rfc2136[type].server, rfc2136[type].key, rfc2136[type].commands);
           }
+        }catch(e){
+          elevenLogJSON('error', {nsupdate:{exception:e.toString()}});
+        }
+      }
+    }
+  }
 
-          resolve(true);
+  async #rfc2136knownRecord(server, nsupdate){
+    const matches = nsupdate.match(/update add (\S+) \d+ (\S+) (\S+)/i);
+    if(matches && matches.length >= 4){
+      try{
+        const record = await dig(server, matches[2], matches[1]);
+        return((record.match(new RegExp(matches[3], 'ig'))));
+      }catch(e){
+        return(false);
+      }
+    }    
+  }
+
+  async #webhook(container){
+    try{
+      await fetch(this.#config.webhook.url, {method:(
+        (container.start) ? 'PUT' : 'DELETE'
+      ), body:JSON.stringify(container), headers:this.#config.webhook.headers, signal:AbortSignal.timeout(2500)});
+    }catch(e){
+      elevenLogJSON('error', {webhook:{exception:e.toString()}});
+    }
+  }
+}
+
+class Worker{
+  run = false;
+  #fork;
+  #config;
+  #parent;
+  log = {
+    disconnect:false,
+  }
+
+  constructor(config, node, parent){
+    this.#config = {
+      tls:config.tls,
+      poll:config.poll.interval,
+      ping:config.ping.interval,
+      port:config.port,
+      node:node,
+    };
+    this.#parent = parent;
+  }
+
+  async fork(){
+    return(new Promise((resolve, reject) => {
+      this.#fork = fork(`${process.env.APP_ROOT}/worker.js`, [JSON.stringify(this.#config)], {stdio: 'inherit'});
+      this.#fork.on('spawn', () =>{
+        this.run = true;
+        resolve();
+      });
+      this.#fork.on('error', () =>{
+        this.run = false;
+        reject();
+      });
+      this.#fork.on('close', (code) =>{
+        this.run = false;
+      });
+      this.#fork.on('message', (message) =>{
+        if(message.error){
+          if(!this.log.disconnect){
+            elevenLogJSON('error', {fork:message.error});
+          }
+        }else{
+          this.run = true;
+          this.log.disconnect = false;
+          if(message?.labels){
+            this.#parent.inspect.apply(this.#parent, [message]);
+          }
         }
       });
     }));
   }
 }
 
-new Labels().watch();
+new Labels().run();

rootfs/labels/nsupdate.js

@@ -0,0 +1,33 @@
+const { spawn } = require('node:child_process');
+const { elevenLogJSON } = require('/labels/lib/util.js');
+
+exports.nsupdate = async(server, key, commands) => {
+
+  commands.unshift(`server ${server}`);
+  commands.push('send');
+  commands.push('quit');
+
+  return(new Promise((resolve, reject) => {
+    elevenLogJSON('debug', {method:'nsupdate()', params:{server:server, key:'******', commands:commands}});
+    const nsupdate = spawn('/usr/bin/nsupdate', ['-y', key]);
+    const io = {stdout:'', stderr:''};
+    nsupdate.stderr.on('data', data => {io.stderr += data.toString()});
+    nsupdate.stdout.on('data', data => {io.stdout += (data.toString()).replace(/[\r\n]*$/ig, '')});
+    nsupdate.on('error', error => {reject(error)});
+    nsupdate.on('close', code =>{
+      if(code === 0){
+        if(io.stderr.length > 0){
+          reject(io.stderr);
+        }else{
+          resolve(io.stdout);
+        }
+      }else{
+        reject(io.stderr);
+      }
+    });
+    for(const command of commands){
+      nsupdate.stdin.write(`${command}\n`);
+    }
+    nsupdate.stdin.end();
+  }));
+}

rootfs/labels/worker.js

@@ -0,0 +1,149 @@
+const fs = require('fs');
+const Docker = require('dockerode');
+const args = process.argv.slice(2);
+
+process
+  .on('unhandledRejection', (e, p) => {
+    console.error(e, p);
+    process.send({error:e.toString()});
+  })
+  .on('uncaughtException', e => {
+    console.error(e);
+    process.send({error:e.toString()});
+  });
+
+class Worker{
+  #config;
+  #docker;
+  #interval = {poll:false, ping:false};
+
+  constructor(config){
+    this.#config = config;
+    this.#docker = new Docker({
+      protocol:'https',
+      host:this.#config.node,
+      port:this.#config.port,
+      ca:fs.readFileSync(this.#config.tls.ca),
+      cert:fs.readFileSync(this.#config.tls.crt),
+      key:fs.readFileSync(this.#config.tls.key),
+      timeout:parseInt(this.#config.timeout*1000)
+    });
+  }
+
+  async run(){
+    try{
+      this.#docker.getEvents({}, (error, data) => {
+        if(!error){
+          data.on('data', async(chunk) =>{
+            const response = chunk.toString('utf8').replace(',"ti"', '');
+            try{
+              const event = JSON.parse(response);
+              if(/Container/i.test(event?.Type) && /^(start|die)$/i.test(event?.status)){
+                this.#labels(event.id, event.status);
+              }
+            }catch(e){
+              //JSON parse error
+            }
+          });
+        }else{
+          process.send({error:error.toString()});
+        }
+      });
+
+      setInterval(async()=>{
+        if(!this.#interval.poll){
+          this.#interval.poll = true;
+          try{
+            await this.#poll();
+          }catch(e){
+            process.send({error:e.toString()});
+          }finally{
+            this.#interval.poll = false;
+          }
+        }
+      }, this.#config.poll*1000);
+
+      setInterval(async()=>{
+        if(!this.#interval.ping){
+          this.#interval.ping = true;
+          try{
+            await this.#ping();
+          }catch(e){
+            process.send({error:e.toString()});
+          }finally{
+            this.#interval.ping = false;
+          }
+        }
+      }, this.#config.ping*1000);
+
+      await this.#ping();
+      await this.#poll();
+
+    }catch(e){
+      process.send({error:e.toString()});
+    }
+  }
+
+  async #poll(){
+    try{
+      await this.#docker.listContainers((error, containers) => {
+        if(!error){
+          containers.forEach(async(container) => {
+            this.#labels(container.Id, 'poll');
+          });
+        }else{
+          process.send({error:e.toString()});
+        }
+      });
+    }catch(e){
+      process.send({error:e.toString()});
+    }
+  }
+
+  async #ping(){
+    try{
+      await this.#docker.ping();
+    }catch(e){
+      process.exit(1);
+    }
+  }
+
+  async #labels(id, event){
+    try{
+      const container = this.#docker.getContainer(id);
+      container.inspect(async(error, data) => {
+        if(!error){
+          const result = {
+            name:(data?.Name || data?.id).replace(/^\//i, ''),
+            event:event,
+            labels:{},
+            start:(/start|poll/i.test(event)) ? true : false,
+            worker:{
+              node:this.#config.node,
+              port:this.#config.port
+            },
+          };
+          for(const label in data?.Config?.Labels){
+            if(/traefik\/|rfc2136\//i.test(label)){
+              result.labels[label] = data.Config.Labels[label];
+            }
+          }
+          process.send(result);
+        }else{
+          throw(error);
+        }
+      });
+    }catch(e){
+      process.send({error:e.toString()});
+    }
+  }
+}
+
+if(Array.isArray(args) && args.length > 0){
+  try{
+    new Worker(JSON.parse(args)).run();
+  }catch(e){
+    process.send({error:e.toString()});
+    process.exit(1);
+  }
+}