Architecture (orchestration?) of services in Docker - how to do it right?

Question

Docker

There is a classic arrangement of services in docker-compose:

3 services:
- load-balancer
- app
- db

And at some point I need several app instances .

Copy-paste in docker-compose
- app
on
- app01
...
- appXY something
is clearly not what we would

like.

Moreover, potentially, new apps can be in another data center (probably, this is a question "with an asterisk). The

question is not how to do it cool / automatically.
I can raise each service "by hand", if any simple solution for "hands"

PS.k8s do not offer (in search of simpler ways).

Answer 1

If the services are
docker-compose up --scale service-name=2
of the same type - if we spread the stack between different docker hosts, in addition, but do not want k8s - well, Docker Swarm

Answer 2

there can be more than one balancer.
Global balancer - spreads across data centers, smaller one - across instances inside the data center.
In the case of a cuber, an external balancer scatters across clusters, an internal service inside a cluster is already distributed across pods