Stop deploying Docker containers by hand. It’s embarrassing.
I caught a junior admin the other day SSH-ing into a live production node to run docker restart web_01. I nearly unplugged his keyboard. In 2015, if you are managing Docker hosts manually, you aren't doing DevOps—you're just playing Russian Roulette with your uptime.
The container revolution is here. Docker 1.7 just dropped, and we finally have tools that promise to turn our messy collection of shell scripts into actual infrastructure. But the landscape is fragmented. You have Google pushing Kubernetes, Docker Inc. pushing Swarm, and the old guard swearing by Apache Mesos.
I’ve spent the last month benchmarking these orchestrators on our CoolVDS infrastructure in Oslo. We pushed them until they broke, measured latency to the NIX (Norwegian Internet Exchange), and looked at the one metric that actually matters: stability under load.
The Contenders
1. Kubernetes (The Google Juggernaut)
Let's be honest: Kubernetes is intimidating. It’s currently hitting v1.0, and while the promise of Google-scale infrastructure is tempting, the learning curve is a vertical wall. It introduces concepts like Pods, ReplicationControllers, and Services that completely abstract away the networking.
The Good: Self-healing is real. If a node dies, Kubernetes reschedules the pods elsewhere instantly.
The Bad: It's heavy. Running the Kubelet, API server, and etcd on a small VPS is a waste of RAM.
Pro Tip: If you are running Kubernetes, do not skimp on etcd performance. It is I/O sensitive. We found that running etcd on standard SSDs caused cluster timeouts. You need NVMe storage (like our High-Performance CoolVDS instances) or you will suffer from split-brain scenarios during leader election.
2. Docker Swarm (The Native Choice)
Swarm is the new kid on the block (still in beta/early release). It turns a pool of Docker hosts into a single, virtual Docker host. The appeal is obvious: you can use the standard Docker CLI.
# Point your client to the Swarm manager
export DOCKER_HOST=tcp://192.168.1.50:4000
# Run it just like a local container
docker run -d -p 80:80 nginxThe Good: Zero learning curve if you know Docker.
The Bad: It lacks the advanced scheduling and self-healing of Kubernetes. It’s dumb clustering.
3. Apache Mesos + Marathon
This is what Twitter and Airbnb use. It’s battle-hardened. It abstracts CPU, memory, storage, and other compute resources away from machines.
The Verdict: Unless you are running thousands of nodes, Mesos is overkill. It’s an operational nightmare to set up compared to Swarm.
The Infrastructure Bottleneck: I/O Wait
Here is the dirty secret of container orchestration: It murders your disk I/O.
When you launch 50 containers simultaneously, they all hammer the filesystem to read layers and write logs. If you are on a cheap budget VPS with shared spinning disks (HDD) or oversold SSDs, your iowait will spike to 90%, and the orchestrator will mark the node as "Unhealthy" because it stopped responding to heartbeats.
This is where virtualization type matters.
| Feature | OpenVZ (Legacy) | KVM (CoolVDS Standard) |
|---|---|---|
| Kernel | Shared with host | Dedicated Kernel |
| Docker Support | Hackish (older kernel issues) | Native & Stable |
| Isolation | Weak (Noisy neighbors) | Strong (Hardware virtualization) |
We strictly use KVM at CoolVDS. Why? Because Docker interacts directly with kernel namespaces and cgroups. On OpenVZ, you are stuck with the host's kernel version (often ancient 2.6.32), which breaks modern Docker features. With KVM, you can install the latest Ubuntu 14.04 or CoreOS and run a kernel that actually supports OverlayFS.
Data Sovereignty: The Norwegian Advantage
We all know the regulatory climate is heating up. With the ongoing debates in the EU regarding data privacy and the strict stance of Datatilsynet here in Norway, knowing exactly where your data physically sits is paramount.
When you spin up a cluster on the big US clouds, you often don't know if your volume is in Frankfurt, Dublin, or replicated to a backup node in Virginia. With CoolVDS, your data stays in our Oslo datacenter. Low latency to Norwegian users (sub-2ms via NIX) and full compliance with the Personal Data Act (Personopplysningsloven).
Final Recommendation
If you are a small team today, stick to Docker Swarm or simpler Compose setups. It works, and it doesn't require a dedicated Ops team.
If you are scaling up and need resilience, Kubernetes is the future—but only if your infrastructure can handle it. Don't try to run K8s on cheap shared hosting. You need dedicated resources.
Ready to build your cluster?
Stop fighting with noisy neighbors and stealing CPU cycles. Deploy a KVM-based, NVMe-backed instance on CoolVDS today. We have pre-built templates for CoreOS and Ubuntu 14.04 ready to go. You focus on the code; we’ll handle the electrons.