Containerized networking

Using FoundationDB Running FoundationDB
1

Hello,
I’m struggling to understand how the networking works once fdb is running in a container.

Lets take this docker-compose.yml as an example

services:
  foundationdb:
    image: foundationdb/foundationdb:7.3.63
    network_mode: host
    user: root
    init: true
    environment:
      FDB_CLUSTER_FILE: /etc/foundationdb/fdb.cluster
    entrypoint: ["/usr/bin/fdbmonitor"]
    command: '--conffile /var/foundationdb.conf'
    volumes:
      - ./fdb.cluster:/var/fdb.cluster
      - ./foundationdb.conf:/var/foundationdb.conf
  fdb-ops:
    build: .
    network_mode: host
    environment:
      FDB_CLUSTER_FILE: /etc/foundationdb/fdb.cluster
    volumes:
      - ./fdb.cluster:/etc/foundationdb/fdb.cluster
  webserver:
    image: nginx:alpine
    network_mode: host
    container_name: simple-webserver

fdb.cluster:

docker:docker@127.0.0.1:4600

foundationdb.conf:

[fdbmonitor]


[general]
restart_delay = 60
cluster_file = /var/fdb.cluster

[fdbserver]
command = /usr/bin/fdbserver
public_address = 127.0.0.1:$ID
listen_address = public
datadir = /var/lib/foundationdb/data/$ID
locality_machineid = test
locality_dcid = test1
trace_format = json

[fdbserver.4600]

All of this is running on host networking.

I would want to reach the cluster from the fdb-ops container.

I can reach the webserver from the fdb-ops container using curl localhost:80 but it doesn’t seem like I’m able to reach the fdb cluster where I expect it to be on localhost:4600. Why?

From the host machine I see the process is listening on

tcp   LISTEN    0      128                127.0.0.1:4600           0.0.0.0:*      users:(("fdbserver",pid=393730,fd=14))

I cant even access it when I try from inside the fdb container

bash-5.1# fdbcli -C /var/fdb.cluster 
Using cluster file `/var/fdb.cluster'.
^CERROR: Asynchronous operation cancelled (1101)
bash-5.1# cat /var/fdb.cluster 
docker:docker@127.0.0.1:4600

What am I missing in my understanding here?