OpenFaaS Edge is a distribution of OpenFaaS Standard that runs without Kubernetes, on a single host or VM.
We created OpenFaaS Edge (aka faasd-pro) as an antidote to the constant churn, change, and complexity of Kubernetes. It is designed to be simple to operate, easy to understand, and reliable so that it can be redistributed as part of an appliance or edge device.
In this post, we’ll explore some new commands added to the faasd binary for managing services, then I’ll show you how stateful services with via the docker-compose.yaml.
Finally, I’ll show you how the arkade tool can be used to upgrade the versions of the container images referenced in the YAML file, and how to ignore certain images if you want to hold them at a specific version.
Introducing the new service commands
The faasd binary for OpenFaaS Edge has a new set of commands that allow you to manage the services defined in the docker-compose.yaml file. These commands are available in OpenFaaS Edge, and they are designed to make it easier to manage stateful services.
faasd service list- Lists the status of each service including its age and uptimefaasd service logs- Displays the logs for a given servicefaasd service restart- Restarts a given servicefaasd service top- Shows the CPU and memory usage of each service
A simpler version of the service logs command was added to faasd CE.
faasd service list
The faasd service list command lists all the services defined in the docker-compose.yaml file. This command is useful for getting an overview of the services that are running on your OpenFaaS Edge instance.
$ faasd service list
NAME IMAGE CREATED STATUS
cron-connector ghcr.io/openfaasltd/cron-connector:0.2.9 23 seconds ago running (23 seconds)
faas-idler ghcr.io/openfaasltd/faas-idler:0.5.6 23 seconds ago running (23 seconds)
gateway ghcr.io/openfaasltd/gateway:0.4.38 23 seconds ago running (23 seconds)
nats docker.io/library/nats:2.10.26 24 seconds ago running (24 seconds)
prometheus docker.io/prom/prometheus:v3.2.1 23 seconds ago running (23 seconds)
queue-worker ghcr.io/openfaasltd/jetstream-queue-worker:0.3.46 23 seconds ago running (23 seconds)
Note that the IP address will change between restarts.
faasd service logs
The faasd service logs command displays the logs for a given service. This command is useful for debugging and troubleshooting issues with your services.
You can use various flags which you may recognise from docker logs, journalctl or kubectl logs:
$ faasd service logs gateway
$ faasd service logs gateway -f
$ faasd service logs gateway --lines 1000
$ faasd service logs gateway --since 1h
$ faasd service logs gateway --since-time "2025-03-18T12:00:00Z"
faasd service top
The faasd service top shows the RAM and CPU usage of each service, so you can keep an eye on whether your services will continue to fit on the host.
$ faasd service top
NAME PID CPU (Cores) Memory
prometheus 5870 2m 50 MB
gateway 5976 2m 12 MB
nats 5759 2m 4.3 MB
cron-connector 6082 0m 5.1 MB
queue-worker 6184 0m 6.3 MB
faas-idler 6493 0m 7.3 MB
faasd service restart
The faasd service restart command restarts a given service.
Whilst this command does not reload any changes from the docker-compose.yaml file, it will stop and restart the service. This is useful if you hadn’t created a volume mount with the right permissions, the image you were using was not yet pushed to the registry, or there was a race condition or crash of your service.
To reload the compose file, run sudo systemctl restart faasd instead.
Perhaps you noticed an error with the faas-idler service and need to restart it?
First, we check the logs to see when it started:
$ faasd service logs faas-idler
OpenFaaS Pro: faas-idler (classic scale-to-zero) Version: 0.5.6 Commit: a2fa75c6c82297d110e4c1922ead2df77c2b3cce
2025/03/18 12:48:08 read-only mode: false
Then we restart it
$ faasd service restart faas-idler
Next, we can check the running time, and see that it’s more recent than the other parts of the stack:
$ sudo faasd service list
NAME IMAGE CREATED STATUS
cron-connector ghcr.io/openfaasltd/cron-connector:0.2.9 2 minutes ago running (2 minutes)
faas-idler ghcr.io/openfaasltd/faas-idler:0.5.6 2 minutes ago running (43 seconds)
New features for the docker-compose.yaml file
Disable a service for a period of time, whilst retaining it in the file:
cron-connector:
deploy:
replicas: 0
Enable automatic restarts for a service such as nats:
nats:
restart: "always"
By default, services that exit will not be restarted unless you run sudo systemctl restart faasd.
How the docker-compose.yaml file works
Since OpenFaaS Edge runs on a VM, without Kubernetes, we needed a way to define the core services that make up the stack the gateway, NATS, Prometheus and the queue-worker. Docker’s Compose specification was a convenient way to do this because it uses a syntax that’s easy to understand and familiar to many developers who have worked with Docker at some point in their career.
Every installation comes with a pre-defined file, which contains definitions for the OpenFaaS gateway, queue-worker, cron-connectors, NATS and Prometheus. Typically you’d only change this file if you wanted to update a setting like the maximum timeout for functions or what version of an image you wanted to run.
Here’s how NATS can be defined in the stack for faasd CE:
services:
nats:
image: docker.io/library/nats:2.10.26
user: "65534"
restart: "always"
command:
- "/nats-server"
- "-js"
- "-sd=/nats"
volumes:
- type: bind
source: ./nats
target: /nats
We can also expose the TCP port for NATS on a given adapter, or just access it from the Linux bridge that is created by faasd.
ports:
- "127.0.0.1:4222:4222"
Service discovery is relatively simple. Each service created by this file can look up other containers by name from a /etc/hosts file that is injected dynamically.
So the code in the OpenFaaS gateway can simply open a TCP connection to nats:4222 and it will be routed to the NATS container.
All services within the compose file are already stateful in that they are run longing, and can write to their filesystem. However, if you want their data to survive restarts, then you can attach volumes to them just like with docker run -v.
For Prometheus, we can add a volume to store its Time Series Data Base (TSDB) on the host machine:
prometheus:
image: docker.io/prom/prometheus:v3.2.1
user: "65534"
restart: "always"
volumes:
- type: bind
source: ./prometheus.yml
target: /etc/prometheus/prometheus.yml
- type: bind
source: ./prometheus
target: /prometheus
cap_add:
- CAP_NET_RAW
ports:
- "127.0.0.1:9090:9090"
We’ve also bind-mounted the prometheus.yml file so that we can change the configuration without having to build a custom image.
How to update images in the docker-compose.yaml file
The arkade tool can be used to check for newer images and upgrade the image tags within the docker-compose.yaml file.
cd /var/lib/faasd
arkade chart upgrade --file ./docker-compose.yaml --write --verbose
Example output:
root@build-1:/var/lib/faasd# arkade chart upgrade --file ./docker-compose.yaml --write --verbose
2025/03/18 12:30:57 Verifying images in: ./docker-compose.yaml
2025/03/18 12:30:57 Found 6 images
2025/03/18 12:30:57 [ghcr.io/openfaasltd/gateway] 0.4.38 => 0.4.39
If you want to hold the version for a certain service, such as postgresql, then you can create a file alongside the docker-compose.yaml which will be read by arkade:
/var/lib/faasd/arkade.yaml
/var/lib/faasd/docker-compose.yaml
Add the full path to each image you want arkade chart upgrade to ignore, for example:
ignore:
- services.postgresql.image
Then run sudo systemctl restart faasd to apply the changes.
Conclusion
We’ve added a new set of commands to help you manage and monitor services with OpenFaaS Edge, along with two new features for the compose file (restart policies and disabling services).
We also took a look at a couple of examples of how to define services in the docker-compose.yaml file using the NATS and Prometheus services from the OpenFaaS Edge YAML file. You can inspect your local YAML file at /var/lib/faasd/docker-compose.yaml to see how the other services are set up.
For additional examples of how to define services in the docker-compose.yaml file, please refer to Serverless For Everyone Else which is the handbook for faasd CE and OpenFaaS Edge. You’ll find detailed examples of how to write functions using Node.js and how to manage additional services such as Grafana, Postgresql, and InfluxDB.
Want to try it out?
For personal, non-commercial use, you have two options:
- faasd CE - free for 15 functions
- OpenFaaS Edge - get free access when you sponsor @openfaas via GitHub for 25 USD/mo or higher
For commercial use:
- faasd CE - 1x installation for a 60 day trial or PoC
- OpenFaaS Edge - purchase a license and run up to 250 functions with various OpenFaaS Pro features included
Alex Ellis
Founder of @openfaas.
