rclone/docs/content/azureblob.md

---
title: "Microsoft Azure Blob Storage"
description: "Rclone docs for Microsoft Azure Blob Storage"
---

{{< icon "fab fa-windows" >}} Microsoft Azure Blob Storage
-----------------------------------------

Paths are specified as `remote:container` (or `remote:` for the `lsd`
command.)  You may put subdirectories in too, e.g.
`remote:container/path/to/dir`.

Here is an example of making a Microsoft Azure Blob Storage
configuration.  For a remote called `remote`.  First run:

     rclone config

This will guide you through an interactive setup process:

```
No remotes found - make a new one
n) New remote
s) Set configuration password
q) Quit config
n/s/q> n
name> remote
Type of storage to configure.
Choose a number from below, or type in your own value
[snip]
XX / Microsoft Azure Blob Storage
   \ "azureblob"
[snip]
Storage> azureblob
Storage Account Name
account> account_name
Storage Account Key
key> base64encodedkey==
Endpoint for the service - leave blank normally.
endpoint> 
Remote config
--------------------
[remote]
account = account_name
key = base64encodedkey==
endpoint = 
--------------------
y) Yes this is OK
e) Edit this remote
d) Delete this remote
y/e/d> y
```

See all containers

    rclone lsd remote:

Make a new container

    rclone mkdir remote:container

List the contents of a container

    rclone ls remote:container

Sync `/home/local/directory` to the remote container, deleting any excess
files in the container.

    rclone sync -i /home/local/directory remote:container

### --fast-list ###

This remote supports `--fast-list` which allows you to use fewer
transactions in exchange for more memory. See the [rclone
docs](/docs/#fast-list) for more details.

### Modified time ###

The modified time is stored as metadata on the object with the `mtime`
key.  It is stored using RFC3339 Format time with nanosecond
precision.  The metadata is supplied during directory listings so
there is no overhead to using it.

### Restricted filename characters

In addition to the [default restricted characters set](/overview/#restricted-characters)
the following characters are also replaced:

| Character | Value | Replacement |
| --------- |:-----:|:-----------:|
| /         | 0x2F  | ／           |
| \         | 0x5C  | ＼           |

File names can also not end with the following characters.
These only get replaced if they are the last character in the name:

| Character | Value | Replacement |
| --------- |:-----:|:-----------:|
| .         | 0x2E  | ．          |

Invalid UTF-8 bytes will also be [replaced](/overview/#invalid-utf8),
as they can't be used in JSON strings.

### Hashes ###

MD5 hashes are stored with blobs.  However blobs that were uploaded in
chunks only have an MD5 if the source remote was capable of MD5
hashes, e.g. the local disk.

### Authenticating with Azure Blob Storage

Rclone has 3 ways of authenticating with Azure Blob Storage:

#### Account and Key

This is the most straight forward and least flexible way.  Just fill
in the `account` and `key` lines and leave the rest blank.

#### SAS URL

This can be an account level SAS URL or container level SAS URL.

To use it leave `account`, `key` blank and fill in `sas_url`.

An account level SAS URL or container level SAS URL can be obtained
from the Azure portal or the Azure Storage Explorer.  To get a
container level SAS URL right click on a container in the Azure Blob
explorer in the Azure portal.

If you use a container level SAS URL, rclone operations are permitted
only on a particular container, e.g.

    rclone ls azureblob:container

You can also list the single container from the root. This will only
show the container specified by the SAS URL.

    $ rclone lsd azureblob:
    container/

Note that you can't see or access any other containers - this will
fail

    rclone ls azureblob:othercontainer

Container level SAS URLs are useful for temporarily allowing third
parties access to a single container or putting credentials into an
untrusted environment such as a CI build server.

### Multipart uploads ###

Rclone supports multipart uploads with Azure Blob storage.  Files
bigger than 256MB will be uploaded using chunked upload by default.

The files will be uploaded in parallel in 4MB chunks (by default).
Note that these chunks are buffered in memory and there may be up to
`--transfers` of them being uploaded at once.

Files can't be split into more than 50,000 chunks so by default, so
the largest file that can be uploaded with 4MB chunk size is 195GB.
Above this rclone will double the chunk size until it creates less
than 50,000 chunks.  By default this will mean a maximum file size of
3.2TB can be uploaded.  This can be raised to 5TB using
`--azureblob-chunk-size 100M`.

Note that rclone doesn't commit the block list until the end of the
upload which means that there is a limit of 9.5TB of multipart uploads
in progress as Azure won't allow more than that amount of uncommitted
blocks.

{{< rem autogenerated options start" - DO NOT EDIT - instead edit fs.RegInfo in backend/azureblob/azureblob.go then run make backenddocs" >}}
### Standard Options

Here are the standard options specific to azureblob (Microsoft Azure Blob Storage).

#### --azureblob-account

Storage Account Name (leave blank to use SAS URL or Emulator)

- Config:      account
- Env Var:     RCLONE_AZUREBLOB_ACCOUNT
- Type:        string
- Default:     ""

#### --azureblob-key

Storage Account Key (leave blank to use SAS URL or Emulator)

- Config:      key
- Env Var:     RCLONE_AZUREBLOB_KEY
- Type:        string
- Default:     ""

#### --azureblob-sas-url

SAS URL for container level access only
(leave blank if using account/key or Emulator)

- Config:      sas_url
- Env Var:     RCLONE_AZUREBLOB_SAS_URL
- Type:        string
- Default:     ""

#### --azureblob-use-emulator

Uses local storage emulator if provided as 'true' (leave blank if using real azure storage endpoint)

- Config:      use_emulator
- Env Var:     RCLONE_AZUREBLOB_USE_EMULATOR
- Type:        bool
- Default:     false

### Advanced Options

Here are the advanced options specific to azureblob (Microsoft Azure Blob Storage).

#### --azureblob-endpoint

Endpoint for the service
Leave blank normally.

- Config:      endpoint
- Env Var:     RCLONE_AZUREBLOB_ENDPOINT
- Type:        string
- Default:     ""

#### --azureblob-upload-cutoff

Cutoff for switching to chunked upload (<= 256MB).

- Config:      upload_cutoff
- Env Var:     RCLONE_AZUREBLOB_UPLOAD_CUTOFF
- Type:        SizeSuffix
- Default:     256M

#### --azureblob-chunk-size

Upload chunk size (<= 100MB).

Note that this is stored in memory and there may be up to
"--transfers" chunks stored at once in memory.

- Config:      chunk_size
- Env Var:     RCLONE_AZUREBLOB_CHUNK_SIZE
- Type:        SizeSuffix
- Default:     4M

#### --azureblob-list-chunk

Size of blob list.

This sets the number of blobs requested in each listing chunk. Default
is the maximum, 5000. "List blobs" requests are permitted 2 minutes
per megabyte to complete. If an operation is taking longer than 2
minutes per megabyte on average, it will time out (
[source](https://docs.microsoft.com/en-us/rest/api/storageservices/setting-timeouts-for-blob-service-operations#exceptions-to-default-timeout-interval)
). This can be used to limit the number of blobs items to return, to
avoid the time out.

- Config:      list_chunk
- Env Var:     RCLONE_AZUREBLOB_LIST_CHUNK
- Type:        int
- Default:     5000

#### --azureblob-access-tier

Access tier of blob: hot, cool or archive.

Archived blobs can be restored by setting access tier to hot or
cool. Leave blank if you intend to use default access tier, which is
set at account level

If there is no "access tier" specified, rclone doesn't apply any tier.
rclone performs "Set Tier" operation on blobs while uploading, if objects
are not modified, specifying "access tier" to new one will have no effect.
If blobs are in "archive tier" at remote, trying to perform data transfer
operations from remote will not be allowed. User should first restore by
tiering blob to "Hot" or "Cool".

- Config:      access_tier
- Env Var:     RCLONE_AZUREBLOB_ACCESS_TIER
- Type:        string
- Default:     ""

#### --azureblob-disable-checksum

Don't store MD5 checksum with object metadata.

Normally rclone will calculate the MD5 checksum of the input before
uploading it so it can add it to metadata on the object. This is great
for data integrity checking but can cause long delays for large files
to start uploading.

- Config:      disable_checksum
- Env Var:     RCLONE_AZUREBLOB_DISABLE_CHECKSUM
- Type:        bool
- Default:     false

#### --azureblob-memory-pool-flush-time

How often internal memory buffer pools will be flushed.
Uploads which requires additional buffers (f.e multipart) will use memory pool for allocations.
This option controls how often unused buffers will be removed from the pool.

- Config:      memory_pool_flush_time
- Env Var:     RCLONE_AZUREBLOB_MEMORY_POOL_FLUSH_TIME
- Type:        Duration
- Default:     1m0s

#### --azureblob-memory-pool-use-mmap

Whether to use mmap buffers in internal memory pool.

- Config:      memory_pool_use_mmap
- Env Var:     RCLONE_AZUREBLOB_MEMORY_POOL_USE_MMAP
- Type:        bool
- Default:     false

#### --azureblob-encoding

This sets the encoding for the backend.

See: the [encoding section in the overview](/overview/#encoding) for more info.

- Config:      encoding
- Env Var:     RCLONE_AZUREBLOB_ENCODING
- Type:        MultiEncoder
- Default:     Slash,BackSlash,Del,Ctl,RightPeriod,InvalidUtf8

{{< rem autogenerated options stop >}}
### Limitations ###

MD5 sums are only uploaded with chunked files if the source has an MD5
sum.  This will always be the case for a local to azure copy.

`rclone about` is not supported by the Microsoft Azure Blob storage backend. Backends without
this capability cannot determine free space for an rclone mount or
use policy `mfs` (most free space) as a member of an rclone union
remote.

See [List of backends that do not support rclone about](https://rclone.org/overview/#optional-features)
See [rclone about](https://rclone.org/commands/rclone_about/)

### Azure Storage Emulator Support ###
You can test rclone with storage emulator locally, to do this make sure azure storage emulator
installed locally and set up a new remote with `rclone config` follow instructions described in
introduction, set `use_emulator` config as `true`, you do not need to provide default account name
or key if using emulator.