Layer 3 · self-hosting reality check
What it actually takes to self-host Zabbix
The docs say 2 GB. In practice you want 4 GB for a few hundred hosts, and the database wants more. Here is the honest version — real requirements, real monthly cost, what you will be maintaining, and the one thing that catches people out.
Usually reached from Datadog alternatives, where Zabbix is one of the picks.
Wondering whether you need to at all? Is Datadog free? — what the free tier actually allows, and where the wall is.
| RAM — documented minimum | 2 GB |
|---|---|
| RAM — what it really needs | 4 GB for a few hundred hosts, and the database wants more |
| CPU | 2 vCPU, 4 with real polling volume |
| Disk | 50 GB and growing — history retention is the driver |
| Monthly cost | $25–50/mo depending on retention |
| Setup time | 3–4 hours |
| How you install it | docker compose or packages: server, frontend, and PostgreSQL or MySQL |
| Ongoing maintenance | Active. Housekeeping and partitioning are ongoing jobs. |
| Where it stops scaling | Tens of thousands of monitored hosts with proxies. It is genuinely enterprise-scale software. |
The thing that catches people out
Zabbix stores every collected value and its housekeeper deletes old rows one at a time, which on a busy install cannot keep up — the database grows until queries crawl. The fix is table partitioning, which is not enabled by default and is significantly easier to set up before the history table is 100 GB than after. Plan retention on day one.
When not to self-host Zabbix
You want metrics-and-dashboards in an afternoon. Zabbix is a full enterprise monitoring system and it asks for that commitment; Prometheus with Grafana is lighter to start.
Every guide here carries this section. A site that only ever tells you to self-host is selling something — the useful answer is sometimes no.
Other Layer 3 self-hosting guides
Common questions
- How much RAM does Zabbix actually need?
- 4 GB for a few hundred hosts, and the database wants more in practice. The documented minimum is 2 GB, which is the figure at which the process starts rather than the figure at which it works under real use. 2 vCPU, 4 with real polling volume alongside it.
- What does self-hosting Zabbix cost per month?
- $25–50/mo depending on retention This is commodity VPS pricing and excludes your time, which is the larger cost for most people — budget for active. Housekeeping and partitioning are ongoing jobs.
- How long does it take to set up Zabbix?
- 3–4 hours, via docker compose or packages: server, frontend, and PostgreSQL or MySQL.
- When should I NOT self-host Zabbix?
- You want metrics-and-dashboards in an afternoon. Zabbix is a full enterprise monitoring system and it asks for that commitment; Prometheus with Grafana is lighter to start.
- What is the most common mistake when self-hosting Zabbix?
- Zabbix stores every collected value and its housekeeper deletes old rows one at a time, which on a busy install cannot keep up — the database grows until queries crawl. The fix is table partitioning, which is not enabled by default and is significantly easier to set up before the history table is 100 GB than after. Plan retention on day one.