# Cluster Missing/Weak Auto-Termination

> ZopNight flags an interactive Databricks cluster whose auto-termination is disabled or set above 120 minutes. An all-purpose cluster left running bills DBUs plus the underlying cloud VMs for every idle minute, and the saving is prorated against that 120-minute ceiling rather than assumed total.

Source: https://zop.dev/integrations/databricks/recommendations/cluster-missing-weak-auto-termination
Updated: 2026-08-19

---

## Two failure modes, one rule

Auto-termination set to zero means disabled, and the cluster runs until somebody stops it. That is
the expensive case: a cluster started for an afternoon's exploration and forgotten bills through
the night and the weekend.

Auto-termination set high, say 480 minutes, is the quieter case. It terminates eventually, but
only after eight idle hours, and it resets on every stray interaction. In practice a cluster with
a long timeout and an open notebook rarely terminates at all.

## The 120-minute ceiling and how the saving is derived

The rule treats 120 minutes as the upper bound for a healthy setting. Above it, or at zero, the
finding fires.

The saving is not the cluster's whole cost. It is prorated: the reported figure scales by
`1 - (120 / configured minutes)`, so a cluster set to 480 minutes yields three-quarters of the
idle cost rather than all of it. That reflects what tightening to the ceiling actually recovers,
not what deleting the cluster would.

## What you are paying for while idle

Databricks charges DBUs for the cluster, and your cloud provider charges separately for the
underlying VMs. An idle all-purpose cluster accrues both. That double meter is why interactive
clusters are consistently the largest avoidable line in a Databricks bill.

## Listing autotermination_minutes per cluster

```bash
databricks clusters list --output json   | jq -r '.clusters[]
      | select(.cluster_source=="UI" or .cluster_source=="API")
      | [.cluster_name, .autotermination_minutes, .state] | @tsv'
```

Anything reporting `0`, or a value above 120, is what this rule sees.

## Where to set it instead

Ten to thirty minutes suits interactive work: long enough to survive a coffee break, short
enough that a forgotten notebook costs little. Cluster policies can enforce a maximum so the
setting is not left to whoever creates the cluster.

Job clusters are exempt from this finding entirely: they terminate when the job ends, which is
the behaviour auto-termination is approximating.