no suitable node - Unable to match constraints services with docker swarm nodes - docker

Question

I execute
sudo docker node ls
And this is my output
ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS ENGINE VERSION
smlsbj3r6qjq7s22cl9cgi1f1 * ip-172-30-0-94 Ready Active Leader 20.10.2
b5e3w8nvrw3kw8q3sg1188439 ip-172-30-0-107 Ready Active 20.10.2
phjkfj09ydvgzztaib2zxcfv9 ip-172-30-0-131 Ready Active 20.10.2
m73z9ikte16klds06upruifji ip-172-30-0-193 Ready Active 20.10.2
So far I get, I know I have one manager and 3 workers. So, if I have a service which has a constraint that match with node.role property of worker nodes, some of them will be elected by docker swarm to execute the containers related to the service itself.
The info of my current service is this:
ID: 5p4hpxmvru9kbwz9y5oymoeq0
Name: elasbit_relay1
Service Mode: Replicated
Replicas: 1
Placement:
Constraints: [node.role!=manager]
UpdateConfig:
Parallelism: 1
On failure: pause
Monitoring Period: 5s
Max failure ratio: 0
Update order: stop-first
RollbackConfig:
Parallelism: 1
On failure: pause
Monitoring Period: 5s
Max failure ratio: 0
Rollback order: stop-first
ContainerSpec:
Image: inputoutput/cardano-node:latest#sha256:02779484dc23731cdbea6388920acc6ddd8e40c03285bc4f9c7572a91fe2ee08
Args: run --topology /configuration/testnet-topology.json --database-path /db --socket-path /db/node.socket --host-addr 0.0.0.0 --port 3001 --config /configuration/testnet-config.json
Init: false
Mounts:
Target: /configuration
Source: /home/ubuntu/cardano-docker-run/testnet
ReadOnly: true
Type: bind
Target: /db
Source: db
ReadOnly: false
Type: volume
Resources:
Endpoint Mode: vip
Ports:
PublishedPort = 12798
Protocol = tcp
TargetPort = 12798
PublishMode = ingress
The key part is [node.role!=manager]. It gives me no suitable node (unsupported platform on 3 nodes; scheduling constraints ….
I tried a lot of ways:
Use docker-compose format (yml) with a constraints list:
deploy:
replicas: 1
placement:
constraints: [node.role==worker]
restart_policy:
condition: on-failure
Use label to nodes.
In all of them I failed. The funny part is, that if I point with some constraint to the node manager, it works! Do I have some typo? Well, I don't see it.
Im using Docker version 20.10.2, build 20.10.2-0ubuntu1~18.04.2.