How to see container ID of a service?

I am trying to follow the tutorial here: (doesn’t allow me to post link)

I was able to create a secret and start a service successfully

$ printf "This is a secret" | docker secret create my_secret_data -
yr3saf1wus8ovauhjvlfugrax
$ docker service  create --name redis --secret my_secret_data redis:alpine
64p8lw9e19q286e4o3x9i1c6x
overall progress: 1 out of 1 tasks
1/1: running   [==================================================>]
verify: Service converged
$ docker service ps redis
ID                  NAME                IMAGE               NODE                DESIRED STATE       CURRENT STATE            ERROR               PORTS
y9pd8u5dlui6        redis.1             redis:alpine        ord                 Running             Running 17 seconds ago

But when I try to get the container ID using the command in that article, I get nothing

$ docker ps --filter name=redis -q

I also tried

$ docker ps --filter name=redis.1 -q

with same result. How can I get container ID of a service? I am running Docker on Linux

$ docker -v
Docker version 18.06.1-ce, build e68fc7a

Also tried following and nothing works

$ docker inspect y9pd8u5dlui6
[
    {
        "ID": "y9pd8u5dlui6anmsnmcjt12xf",
        "Version": {
            "Index": 6405
        },
        "CreatedAt": "2020-01-22T00:32:16.292138626Z",
        "UpdatedAt": "2020-01-22T00:32:24.534124247Z",
        "Labels": {},
        "Spec": {
            "ContainerSpec": {
                "Image": "redis:alpine@sha256:cb9783b1c39bb34f8d6572406139ab325c4fac0b28aaa25d5350495637bb2f76",
                "Init": false,
                "DNSConfig": {},
                "Secrets": [
                    {
                        "File": {
                            "Name": "my_secret_data",
                            "UID": "0",
                            "GID": "0",
                            "Mode": 292
                        },
                        "SecretID": "yr3saf1wus8ovauhjvlfugrax",
                        "SecretName": "my_secret_data"
                    }
                ],
                "Isolation": "default"
            },
            "Resources": {
                "Limits": {},
                "Reservations": {}
            },
            "Placement": {
                "Platforms": [
                    {
                        "Architecture": "amd64",
                        "OS": "linux"
                    },
                    {
                        "OS": "linux"
                    },
                    {
                        "OS": "linux"
                    },
                    {
                        "Architecture": "arm64",
                        "OS": "linux"
                    },
                    {
                        "Architecture": "386",
                        "OS": "linux"
                    },
                    {
                        "Architecture": "ppc64le",
                        "OS": "linux"
                    },
                    {
                        "Architecture": "s390x",
                        "OS": "linux"
                    }
                ]
            },
            "ForceUpdate": 0
        },
        "ServiceID": "64p8lw9e19q286e4o3x9i1c6x",
        "Slot": 1,
        "NodeID": "pea6ipfma4o0jkss3cpsab6pe",
        "Status": {
            "Timestamp": "2020-01-22T00:32:24.493821182Z",
            "State": "running",
            "Message": "started",
            "ContainerStatus": {
                "ContainerID": "ad54d47e86ae9b364571cc688211d40deb626c7cb1f5c4ed6d7705f8fed42167",
                "PID": 47646,
                "ExitCode": 0
            },
            "PortStatus": {}
        },
        "DesiredState": "running"
    }
]
$ docker exec -it ad54d47e86ae9b364571cc688211d40deb626c7cb1f5c4ed6d7705f8fed42167 /bin/bash
Error: No such container: ad54d47e86ae9b364571cc688211d40deb626c7cb1f5c4ed6d7705f8fed42167
$ docker exec -it pea6ipfma4o0jkss3cpsab6pe /bin/bash
Error: No such container: pea6ipfma4o0jkss3cpsab6pe
$ docker exec -it 64p8lw9e19q286e4o3x9i1c6x /bin/bash
Error: No such container: 64p8lw9e19q286e4o3x9i1c6x

The reason above didn’t work was that the container was deployed on the ord node. This can be seen in output of docker service ps redis. When we checked on ord we were able to find the container.

$ docker ps --filter name=redis -q
ad54d47e86ae