Unable to ping Synology from Traefik

Traefik Traefik v2
1

I have had Traefik v2 running for a few days as a container service on my Synology NAS. It has been working perfectly fine and i can successfully browse to my other containerised, and non-containerised services (CCTV, Home Assistant etc) over the public internet via Traefik.

One thing I did notice that when enabling Access.log - it wouldn't show me the real IP of the originating client. Having read solutions online that I should put the Traefik ports in 'Host' mode - this still did not work for me - so I thought I'd create a macvlan network and have Traefik sitting on that network with it's own IP on my LAN. This has worked for me to an extent - I can browse to all but 1 of my services now. The one I can not access over the public internet is my Synology Host!

If I SSH into the Synology - I can ping the IP of my Traefik container fine.
If I SSH into the Traefik container - I can NOT ping the Synology however I can ping everything else on my LAN. I'm not sure what I'm doing wrong here.

The log entry shows: level=debug msg="'502 Bad Gateway' caused by: dial tcp 192.168.0.113:5000: connect: no route to host"

Here's a copy of my compose that stands up Traefik: version: "3.8"services:############ TRAEFIK ################ traefik: - Pastebin.com

Successful ping from Synology (192.168.0.113) to Traefik (.29):

tr1
tr11374×456 74.3 KB

SSH into my Traefik container - unsuccessful ping to Synology (.113) but successful ping to my home router (.1)

tr2
tr21350×711 88.3 KB

Route print of my Synology NAS

Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
default RT-AC68U-5ED8.l 0.0.0.0 UG 0 0 0 eth0
169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth3
169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth2
169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth1
172.17.0.0 0.0.0.0 255.255.0.0 U 0 0 0 docker0
172.18.0.0 0.0.0.0 255.255.0.0 U 0 0 0 docker-54e435ae
172.20.0.0 0.0.0.0 255.255.0.0 U 0 0 0 docker-4a7e0606
192.168.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
192.168.0.28 0.0.0.0 255.255.255.252 U 0 0 0 macvlan0

2

Habe you tried setting only required ports into host mode?

docker-compose.yml:

version: '3.9'

services:
  traefik:
    image: traefik:v2.9
    ports:
      # listen on host ports without ingress network (Docker Swarm)
      - target: 80
        published: 80
        protocol: tcp
        mode: host
      - target: 443
        published: 443
        protocol: tcp
        mode: host
    …

If you have a Load Balancer in front of your setup, check Traefik ProxyProtocol.