CODEWITHSUNDEEP
docker-composesystemdrhel7
Shafique Jamal
Shafique Jamal

Reputation: 1688

systemd: seems like ExecStop script is executed immediately after the start command is run

I am trying to start a docker-compose project as a systemd service on RHEL 7. Here is my systemd script (/etc/systemd/system/wp.service):

[Unit]
Description=wp service with docker compose
Requires=docker.service
After=docker.service

[Service]
EnvironmentFile=/home/ec2-user/projects/wp/project-dir/vars.env
WorkingDirectory=/home/ec2-user/projects/wp/project-dir

# ExecStartPre=/usr/bin/docker-compose down

ExecStart=/usr/bin/docker-compose up -d --build --remove-orphans

# ExecStop=/usr/bin/docker-compose down

[Install]
WantedBy=multi-user.target

When I execute the following command:

sudo systemctl status wp.service

Everything works fine - the containers run and stay running. Here is the output of sudo systemctl status wp.service

Aug 15 03:07:22 ip-172-31-33-87.ec2.internal docker-compose[4185]: ---> Using cache
Aug 15 03:07:22 ip-172-31-33-87.ec2.internal docker-compose[4185]: ---> 7392974149d3
Aug 15 03:07:22 ip-172-31-33-87.ec2.internal docker-compose[4185]: Successfully built 7392974149d3
Aug 15 03:07:22 ip-172-31-33-87.ec2.internal docker-compose[4185]: Successfully tagged foo_wp:latest
Aug 15 03:07:22 ip-172-31-33-87.ec2.internal docker-compose[4185]: Creating mysql ...
Aug 15 03:07:22 ip-172-31-33-87.ec2.internal docker-compose[4185]: [55B blob data]
Aug 15 03:07:23 ip-172-31-33-87.ec2.internal docker-compose[4185]: [37B blob data]

and the containers are up:

[ec2-user@ip-172-31-33-87 ~]$ sudo docker container ls -a
CONTAINER ID        IMAGE                   COMMAND                  CREATED              STATUS                    PORTS                  NAMES
579b52c8e3bc        foo_wp        "docker-entrypoint.s…"   About a minute ago   Up About a minute         0.0.0.0:9101->80/tcp   wp
3c418cfe2b9c        mariadb:10.3.8-bionic   "docker-entrypoint.s…"   About a minute ago   Up About a minute         3306/tcp               mysql

If, however, I uncomment the ExecStop line above (and run docker-compos down and reload the service), then the containers are removed after they are run. The output of the status command is:

   Loaded: loaded (/etc/systemd/system/wp.service; disabled; vendor preset: disabled)
   Active: deactivating (stop) since Wed 2018-08-15 03:12:12 UTC; 7s ago
  Process: 4862 ExecStart=/usr/bin/docker-compose up -d --build --remove-orphans (code=exited, status=0/SUCCESS)
 Main PID: 4862 (code=exited, status=0/SUCCESS);         : 5165 (docker-compose)
    Tasks: 2
   Memory: 19.0M
   CGroup: /system.slice/wp.service
           └─control
             └─5165 /usr/bin/python2 /usr/bin/docker-compose down

Aug 15 03:12:11 ip-172-31-33-87.ec2.internal docker-compose[4862]: Step 3/3 : COPY wordpress/ /var/www/html/
Aug 15 03:12:11 ip-172-31-33-87.ec2.internal docker-compose[4862]: ---> Using cache
Aug 15 03:12:11 ip-172-31-33-87.ec2.internal docker-compose[4862]: ---> 7392974149d3
Aug 15 03:12:11 ip-172-31-33-87.ec2.internal docker-compose[4862]: Successfully built 7392974149d3
Aug 15 03:12:11 ip-172-31-33-87.ec2.internal docker-compose[4862]: Successfully tagged foo_wp:latest
Aug 15 03:12:11 ip-172-31-33-87.ec2.internal docker-compose[4862]: Creating mysql ...
Aug 15 03:12:11 ip-172-31-33-87.ec2.internal docker-compose[4862]: [55B blob data]
Aug 15 03:12:12 ip-172-31-33-87.ec2.internal docker-compose[4862]: [37B blob data]
Aug 15 03:12:12 ip-172-31-33-87.ec2.internal docker-compose[5165]: Stopping wp    ...
Aug 15 03:12:12 ip-172-31-33-87.ec2.internal docker-compose[5165]: Stopping mysql ...

and the containers have been removed:

sudo docker container ls -a
CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS               NAMES
[ec2-user@ip-172-31-33-87 foo]$

It seems as though the systemd service is executing the ExecStop script immediately after the ExecStart script. What could be the cause?

Upvotes: 2

Views: 2460

Answers (1)

NZD
NZD

Reputation: 1970

You are running docker-compose in detached mode (option -d). After starting the containers, docker-compose will daemonise the containers and exit.

Systemd monitors the PID of docker-compose, and when it exits, assumes that your program has stopped and will invoke the ExecStop commands.

Try running it without the -d option.

The reason systemd does this is because you haven't specified the type of your unit and by default it reverts to Type=simple.

See the official documentation for Type and ExecStop.

Upvotes: 6

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