Transmission, but in Kubernetes!

transmission-deployment.yml

kind: Deployment
apiVersion: apps/v1
metadata:
    name: transmission-deployment
    namespace: house-infra
    labels:
        app: transmission
spec:
    replicas: 1
    selector:
        matchLabels:
            app: transmission
    template:
        metadata:
            name: transmission-pod
            namespace: house-infra
            labels:
                app: transmission
        spec:
            containers:
            - name: transmission-container
              image: ghcr.io/linuxserver/transmission
              ports:
              - containerPort: 9091
                protocol: TCP
              - containerPort: 51413
                protocol: TCP
              - containerPort: 51413
                protocol: UDP

              volumeMounts:
              - mountPath: /downloads
                name: downloads-volume
              - mountPath: /config
                name: config-volume
              - mountPath: /watch
                name: watch-volume

              env:
              - name: PUID
                value: "1000"
              - name: PGID
                value: "1000"
              - name: TZ
                value: "America/Los_Angeles"
              - name: USER
                value: "admin"
              - name: PASS
                valueFrom:
                    secretKeyRef:
                        name: transmission-secrets
                        key: transmission-password

            volumes:
            - name: downloads-volume
              hostPath:
                path: /opt/transmission/downloads
                type: DirectoryOrCreate
            - name: config-volume
              hostPath:
                path: /opt/transmission/config
                type: DirectoryOrCreate
            - name: watch-volume
              hostPath:
                path: /opt/transmission/watch
                type: DirectoryOrCreate

---

kind: Service
apiVersion: v1
metadata:
    name: transmission-service
    namespace: house-infra
spec:
    type: NodePort
    selector:
        app: transmission
    ports:
    - protocol: TCP
      name: web-interface
      port: 9091
      nodePort: 9091
    - protocol: TCP
      name: torrent-tcp
      port: 51413
      nodePort: 51413
    - protocol: UDP
      name: torrents-udp
      port: 51413
      nodePort: 51413

transmission-secrets.yml

apiVersion: v1
kind: Secret
metadata:
    name: transmission-secrets
    namespace: house-infra
stringData:
    transmission-password: SecretPass!

There are multiple things that can be happening

1. There could be another firewall (your router) blocking this traffic coming in from the internet.
2. iptables (or something similar) could be enabled on the local box and be filtering traffic. You could try fully disabling the firewall on the kubernetes host. You can use netcat to test UDP connectivity.
3. Use tcpdump either on the host machine or inside of the transmission pod to see what packets are actually being processed.

There are also a lot of discussions around using transmission in containers on their support site: https://discourse.linuxserver.io/tag/transmission

Ok, turns out to be a Suricata rule on my pfSense firewall!

Thank you for your insight!

I am happy you figured it out! Cheers!