I'm curious about the sizes of Docker Swarm deployments compared to what's common in the industry. Currently, at my workplace, our Docker Swarm setup includes 20 nodes, 58 networks, 51 stacks, 294 services, and 429 running containers. I'm interested in how this stacks up against other deployments—how big is your Docker Swarm?
8 Answers
Your cluster rivals the larger Docker EE Swarm setups I handled a few years back. Most larger instances were running on Mesos, and I doubt many are using Swarm anymore as they transition to Kubernetes.
Why stick with Docker Swarm instead of switching to Kubernetes?
I've found that using Docker Compose stacks often saves us more in staffing and cloud costs compared to running Kubernetes if we aren’t using our own hardware.
In a university project, I worked with 2 nodes and briefly 3, managing around 300 containers for a retailer with numerous IoT devices. It was quite the experience!
We reached about 40 nodes back in 2020 before migrating to OpenShift. At that point, we were running 50,000 job containers a month with around 20 stacks.
I used to work with Docker Swarm, but it kind of got overshadowed by Kubernetes as it gained popularity. How's it running for you though? Anyone here done a pros and cons comparison between Docker Swarm and Kubernetes? Sorry for getting off track!
Swarm is working really well for us! Our setup is unique: we own all our hardware, so scaling isn't frequent. When we scale, we usually just add new hardware without taking down services, plus we don’t roll out new services often; it’s pretty much stable after years. The main drawback I've found is that it's harder to find admins experienced in Swarm compared to Kubernetes.
I've managed a 10-node Swarm for a critical system and used various Kubernetes clusters. I enjoy the simplicity of Swarm; it feels a lot like using Docker Compose across multiple nodes. Kubernetes has more features, but Swarm is definitely easier to get started with!
Had a production setup with around 30 nodes, hosting 500-600 stacks, each with at least 3 containers. We typically ran 2 or 3 clusters like that.
We’ve pushed our Swarm to around 35 nodes with 700 containers. Swarm holds up well, but if you're looking for scalability, Kubernetes really simplifies orchestration at a larger scale.
In production, we have 18 nodes, 10 networks, 6 stacks, around 39 services, and about 100 containers. We've been stable for over 6 years!
Our infrastructure is quite stable, and Docker Swarm meets all our needs. We've evaluated Kubernetes numerous times, but it doesn't bring enough benefits for us, just more complexity. As long as that stays the case, we'll keep using Swarm.