which is a step in the right direction, but not what I was going for.
30000 and 30001 are auto assigned ports in that sense
so this is where I figured I'm not understanding the docker swarm networks and/or are making a mistake in how I'm setting it all up. By now, networks are entirely default in my
docker-compose.yml files I use to setup these stacks.
In your docker-compose stack file, make sure you are attaching the service to a network (networks: - net) in the docker-compose.yml example above, and don’t define any ports: under that service. The containers will come up and bind to an ephemeral internal IP address on whatever ports they care to bind on, but those ports won’t be exposed to the outside world.
What is the go to way to share snippets here? Just copy and paste between ``` ?
version: '3.3'
services:
nginx:
image: nginx:latest
environment:
VIRTUAL_HOST: example.com
ports:
- 30001:80
networks:
- default
logging:
driver: json-file
networks:
default:
driver: overlaydocker-compose.yml as it gets set up after I load in my stuff. It basically adds the default network in there for me
the 30001 can be considered
0
what you're saying is I shouldn't bind
ports, and run the default network which is already in overlay mode.
right?
Yeah, I would assume you would just do
ports: - 80:80
instead what happens, and this is where I'm missing what I'm doing wrong, is when I bind
80:80, it becomes available to the entire world and docker swarm, instead of just in this network that I was expecting to be routing to
ah yeah, the containername is interesting; wouldn't you expect this to be at a stack level or something?
considering they're like isolated applications on their own?
basically, if I would grab a
docker-compose.yml from anywhere with a web app; you may assume a port 80 is bound somewhere. However, if there's already another stack that uses it, this won't work. This seems weird to me, as I understand that you'd have to route to that specific virtual network in your swarm (hence; the reverse proxy). But I wasn't expecting it to be swarm wide when you expose a port.
Yes, basically.
In my mind, I have multiple "fake" networks, isolated per stack
In that network you can have containers expose port 80. so your config for appA doesn't touch your config for appB, they can both be using port 80 whatever.
Then you either reverse proxy into the correct network (via IP or generated port? I don't know?), and let the docker swarm loadbalancer take it from there
am I making a mistake in my mental mindmap?
I mean, when I look at my networks topology now in swarmpit; I have
test_default, test2_default (being appA and appB)
and I would expect, they can both have their
port 80 assignment in there.
instead, they seem to give up their private network and influence the entire swarm, instead of just their own personal little stack
am I making any sense at all? :-P
I don’t have any experience there. My experience is that you need to join other stacks into the SAME network in order for them to be able to route to each other. See ‘attachable: true’ within https://github.com/swarmstack/swarmstack/blob/master/docker-compose.yml and then maybe https://github.com/swarmstack/errbot-docker/blob/master/docker-compose-swarmstack.yml for example of a second stack connecting to the first one’s network
Surely they need to expose something to the entire swarm, and that's up to a reverse proxy to figure out then
which is a different situation in which I have a bit more experience myself using nginx
It's just that I can't wrap my head around separating my stacks and containers into their own isolated areas and then having a main manager handle the routing to the correct stack/container
Ah ok that makes a bit more sense to me
but that would mean you wouldn't expose
port 80:80, but have it randomize instead so your proxy can take port 80:80
or have a fixed port per application basically
if you were running a docker swarm, and you wanted to deploy 2 or more separate apps that have no reason to communicate to eachother
how would you go about separating and assigning networks and ports?