`STANDARD` storage class implies more parity than `REDUCED_REDUNDANCY` class. So, `STANDARD` parity drives should be

- Greater than or equal to 2, if `REDUCED_REDUNDANCY` parity is not set.
- Greater than `REDUCED_REDUNDANCY` parity, if it is set.

Parity blocks can not be higher than data blocks, so `STANDARD` storage class parity can not be higher than N/2. (N being total number of drives)

> **This list is non exhaustive, it depends on the operating system and filesystem under use - please consult your operating system vendor for a more comprehensive list of special characters**.

MinIO recommends using Linux operating system for production workloads.

### 3.1 Automatic removal of non current objects versions

A non-current object version is a version which is not the latest for a given object. It is possible to set up an automatic removal of non-current versions when a version becomes older than a given number of days.

e.g., To scan objects stored under `user-uploads/` prefix and remove versions older than one year.

```

	fmt.Println(string(buf))
}
```

It is possible to use an existing buffer with by replacing `New` with `NewBuffer`.


# Blocking vs Non-blocking

The default behavior of the ring buffer is non-blocking, 
meaning that reads and writes will return immediately with an error if the operation cannot be completed.
If you want to block when reading or writing, you must enable it:

```go

# MinIO Grid

The MinIO Grid is a package that provides two-way communication between servers.
It uses a single two-way connection to send and receive messages between servers.

It includes built in muxing of concurrent requests as well as congestion handling for streams.

Requests can be "Single Payload" or "Streamed".

Use the MinIO Grid for:

* Small, frequent requests with low latency requirements.

- All features currently used by your buckets will work as is without any changes
  - SSE (Server Side Encryption)
  - Replication (Server Side Replication)

## Prerequisites

- It is assumed you have users created and configured with relevant access policies, to start with
  use basic "readwrite" canned policy to test all the operations before you finalize on what level
  of restrictions are needed for a user.

Author: Harshavardhana <******@****.***>
Date:   Wed Nov 17 15:49:12 2021 -0800

    heal legacy objects when versioning is enabled after upgrade (#13671)
```

- A security fix must be backported if a customer is affected by it, we have a mechanism in SUBNET to send out notifications to affected customers in such situations, this is a mandatory requirement.

```
commit 99bf4d0c429f04dbd013ba98840d07b759ae1702 (tag: RELEASE.2019-06-15T23-07-18Z)

  periodSeconds: 15
  timeoutSeconds: 10
  successThreshold: 1
  failureThreshold: 3
```

## Cluster probe

### Cluster-writeable probe

The reply is '200 OK' if cluster has write quorum if not it returns '503 Service Unavailable'.

```
curl http://minio1:9001/minio/health/cluster
HTTP/1.1 503 Service Unavailable
Accept-Ranges: bytes
Content-Length: 0
Server: MinIO
Vary: Origin

- MinIO exports Prometheus compatible data by default which is bucket centric as an authorized endpoint at `/minio/v2/metrics/bucket`.

This document explains how to setup Prometheus and configure it to scrape data from MinIO servers.

## Prerequisites

To get started with MinIO, refer [MinIO QuickStart Document](https://min.io/docs/minio/linux/index.html#quickstart-for-linux).

**In our tests we also found ext4 does not honor POSIX O_DIRECT/Fdatasync semantics, ext4 trades performance for consistency guarantees. Please avoid ext4 in your setup.**

**If MinIO distributed setup is using NFS volumes underneath it is not guaranteed MinIO will provide these consistency guarantees since NFS is not strictly consistent (If you must use NFS we recommend that you at least use NFSv4 instead of NFSv3 for relatively better outcomes).**

## Get started