---
title: "Monitoring S3 Buckets"
slug: "monitoring-s3-buckets-tg"
tags: ["5.5"]
updated: 2026-10-27T23:00:54Z
published: 2026-10-27T23:00:54Z
canonical: "docs.vastdata.com/monitoring-s3-buckets-tg"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.vastdata.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Monitoring S3 Buckets

Metrics collected per tenant and per bucket can be queried using the VMS REST API. These metrics enable you to monitor S3 traffic, requests and errors.

Bucket-level metrics are aggregated per bucket every minute and retained for 24 hours.

Tenant-level performance metrics are collected every ten seconds.

## Available Metrics

The following are the metrics that can be queried by external systems using the VMS REST API:

> [!NOTE]
> Note
> 
> Latency is measured in ms.

| Object Type | Class | Metric | Description |
| --- | --- | --- | --- |
| `View` | `BucketViewMetrics` | `head_requests` | The number of HEAD requests. |
|  |  | `put_requests` | The number of PUT requests. |
|  |  | `get_requests` | The number of GET requests. |
|  |  | `post_requests` | The number of POST requests. |
|  |  | `delete_requests` | The number of DELETE requests. |
|  |  | `client_error_responses` | The number of requests for which the server returned a 4xx HTTP error code. |
|  |  | `server_error_responses` | The number of requests for which the server returned a 5xx HTTP error code. |
| Tenant | TenantMetrics | `write_iops__num_samples` | The number of samples of write I/O per second. |
|  |  | `read_bw__num_samples` | The number of samples of bandwidth (uploaded/downloaded bytes per second) for read operations. |
|  |  | `read_md_iops__sum_squares` | The sum of the squares of all samples of read metadata I/O operations per second. |
|  |  | `write_latency__num_samples` | The number of latency samples for write operations. |
|  |  | `write_bw__sum` | The sum of the sampled values of bandwidth (uploaded/downloaded bytes per second) for write operations. |
|  |  | `write_latency__sum_squares` | The sum of the squares of latency samples for write operations. |
|  |  | `read_md_latency__num_samples` | The number of latency samples for metadata read operations. |
|  |  | `read_bw__sum_squares` | The sum of the squares of bandwidth (uploaded/downloaded bytes per second) for read operations. |
|  |  | `read_latency__sum` | The sum of latency samples for read operations. |
|  |  | `write_md_latency__sum` | The sum of latency samples for write metadata operations. |
|  |  | `write_md_iops__num_samples` | The number of samples of metadata write I/O operations per second, |
|  |  | `write_latency__sum` | The sum of latency samples for write operations. |
|  |  | `write_iops__sum` | The sum of the sampled values of write I/O operations per second, |
|  |  | `write_md_latency__num_samples` | The number of latency samples for metadata write operations. |
|  |  | `read_md_iops__sum` | The sum of the sampled values of metadata read I/O operations per second, |
|  |  | `read_bw__sum` | The sum of the sampled values of bandwidth (uploaded/downloaded bytes per second) for read operations. |
|  |  | `read_md_latency__sum` | The sum of latency samples for metadata read operations. |
|  |  | `write_md_iops__sum_squares` | The sum of the squares of all samples of metadata write I/O operations per second. |
|  |  | `read_iops__num_samples` | The number of samples of read I/O operations per second. |
|  |  | `read_iops__sum` | The sum of the sampled values of read I/O operations per second, |
|  |  | `write_bw__num_samples` | The sum of the sampled values of bandwidth (uploaded/downloaded bytes per second) for write operations. |
|  |  | `read_latency__num_samples` | The number of latency samples for read operations. |
|  |  | `write_bw__sum_squares` | The sum of the squares of all samples of bandwidth (uploaded/downloaded bytes per second) for write operations. |
|  |  | `read_iops__sum_squares` | The sum of the squares of all samples of read I/O operations per second. |
|  |  | `write_iops__sum_squares` | The sum of the squares of all samples of write I/O operations per second. |
|  |  | `read_latency__sum_squares` | The sum of the squares of latency samples for read operations. |
|  |  | `read_md_iops__num_samples` | The number of samples of metadata read I/O operations per second. |
|  |  | `write_md_iops__sum` | The sum of the sampled values of metadata write I/O operations per second, |
|  |  | `write_md_latency__sum_squares` | The sum of the squares of latency samples for metadata write operations. |
|  |  | `read_md_latency__sum_squares` | The sum of the squares of latency samples for metadata read operations. |

## How to Query the Metrics

You can use the following VMS REST API endpoints to query the metrics:

- To get object IDs for tenants, send a GET request to the `/tenants/` endpoint.
- To get object IDs for views, send a GET request to the `/views/` endpoint.
- To create a custom analytics report for specified metrics, send a POST request to the `/monitors/` endpoint.
- To query an analytics report: GET request to the `/monitors/{id}/query/` endpoint, where id is the ID of the report.
- To run a query for specified metrics: GET request to the `/monitors/ad_hoc_query/` endpoint.

For information about these endpoints, see the *VAST Management Service (VMS) REST API Documentation*. You can access this documentation at `<VMS IP>/docs`.