Preparing a new repository

The place where your backups will be saved is called a “repository”. This is simply a directory containing a set of subdirectories and files created by restic to store your backups, some corresponding metadata and encryption keys.

To access the repository, a password (also called a key) must be specified. A repository can hold multiple keys that can all be used to access the repository.

This chapter explains how to create (“init”) such a repository. The repository can be stored locally, or on some remote server or service. We’ll first cover using a local repository; the remaining sections of this chapter cover all the other options. You can skip to the next chapter once you’ve read the relevant section here.

For automated backups, restic supports specifying the repository location in the environment variable RESTIC_REPOSITORY. Restic can also read the repository location from a file specified via the --repository-file option or the environment variable RESTIC_REPOSITORY_FILE.

For automating the supply of the repository password to restic, several options exist:

• Setting the environment variable RESTIC_PASSWORD

• Specifying the path to a file with the password via the option --password-file or the environment variable RESTIC_PASSWORD_FILE

• Configuring a program to be called when the password is needed via the option --password-command or the environment variable RESTIC_PASSWORD_COMMAND

The init command has an option called --repository-version which can be used to explicitly set the version of the new repository. By default, the current stable version is used (see table below). The alias latest will always resolve to the latest repository version. Have a look at the design documentation for more details.

The below table shows which restic version is required to use a certain repository version, as well as notable features introduced in the various versions.

Repository version	Required restic version	Major new features	Comment
1	Any
2	0.14.0 or newer	Compression support	Current default

Local

In order to create a repository at /srv/restic-repo, run the following command and enter the same password twice:

$ restic init --repo /srv/restic-repo
enter password for new repository:
enter password again:
created restic repository 085b3c76b9 at /srv/restic-repo
Please note that knowledge of your password is required to access the repository.
Losing your password means that your data is irrecoverably lost.

Warning

Remembering your password is important! If you lose it, you won’t be able to access data stored in the repository.

Warning

On Linux, storing the backup repository on a CIFS (SMB) share or backing up data from a CIFS share is not recommended due to compatibility issues in older Linux kernels. Either use another backend or set the environment variable GODEBUG to asyncpreemptoff=1. Refer to GitHub issue #2659 for further explanations.

SFTP

In order to backup data via SFTP, you must first set up a server with SSH and let it know your public key. Passwordless login is important since automatic backups are not possible if the server prompts for credentials.

Once the server is configured, the setup of the SFTP repository can simply be achieved by changing the URL scheme in the init command:

$ restic -r sftp:user@host:/srv/restic-repo init
enter password for new repository:
enter password again:
created restic repository f1c6108821 at sftp:user@host:/srv/restic-repo
Please note that knowledge of your password is required to access the repository.
Losing your password means that your data is irrecoverably lost.

You can also specify a relative (read: no slash (/) character at the beginning) directory, in this case the dir is relative to the remote user’s home directory.

Also, if the SFTP server is enforcing domain-confined users, you can specify the user this way: user@domain@host.

Note

Please be aware that SFTP servers do not expand the tilde character (~) normally used as an alias for a user’s home directory. If you want to specify a path relative to the user’s home directory, pass a relative path to the SFTP backend.

If you need to specify a port number or IPv6 address, you’ll need to use URL syntax. E.g., the repository /srv/restic-repo on [::1] (localhost) at port 2222 with username user can be specified as

sftp://user@[::1]:2222//srv/restic-repo

Note the double slash: the first slash separates the connection settings from the path, while the second is the start of the path. To specify a relative path, use one slash.

Alternatively, you can create an entry in the ssh configuration file, usually located in your home directory at ~/.ssh/config or in /etc/ssh/ssh_config:

Host foo
    User bar
    Port 2222

Then use the specified host name foo normally (you don’t need to specify the user name in this case):

$ restic -r sftp:foo:/srv/restic-repo init

You can also add an entry with a special host name which does not exist, just for use with restic, and use the Hostname option to set the real host name:

Host restic-backup-host
    Hostname foo
    User bar
    Port 2222

Then use it in the backend specification:

$ restic -r sftp:restic-backup-host:/srv/restic-repo init

Last, if you’d like to use an entirely different program to create the SFTP connection, you can specify the command to be run with the option -o sftp.command="foobar". Alternatively, -o sftp.args allows setting the arguments passed to the default SSH command (ignored when sftp.command is set)

Note

Please be aware that SFTP servers close connections when no data is received by the client. This can happen when restic is processing huge amounts of unchanged data. To avoid this issue add the following lines to the client’s .ssh/config file:

ServerAliveInterval 60
ServerAliveCountMax 240

REST Server

In order to backup data to the remote server via HTTP or HTTPS protocol, you must first set up a remote REST server instance. Once the server is configured, accessing it is achieved by changing the URL scheme like this:

$ restic -r rest:http://host:8000/ init

Depending on your REST server setup, you can use HTTPS protocol, unix socket, password protection, multiple repositories or any combination of those features. The TCP/IP port is also configurable. Here are some more examples:

$ restic -r rest:https://host:8000/ init
$ restic -r rest:https://user:pass@host:8000/ init
$ restic -r rest:https://user:pass@host:8000/my_backup_repo/ init
$ restic -r rest:http+unix:///tmp/rest.socket:/my_backup_repo/ init

The server username and password can be specified using environment variables as well:

$ export RESTIC_REST_USERNAME=<MY_REST_SERVER_USERNAME>
$ export RESTIC_REST_PASSWORD=<MY_REST_SERVER_PASSWORD>

If you use TLS, restic will use the system’s CA certificates to verify the server certificate. When the verification fails, restic refuses to proceed and exits with an error. If you have your own self-signed certificate, or a custom CA certificate should be used for verification, you can pass restic the certificate filename via the --cacert option. It will then verify that the server’s certificate is contained in the file passed to this option, or signed by a CA certificate in the file. In this case, the system CA certificates are not considered at all.

REST server uses exactly the same directory structure as local backend, so you should be able to access it both locally and via HTTP, even simultaneously.

Amazon S3

Restic can backup data to any Amazon S3 bucket. However, in this case, changing the URL scheme is not enough since Amazon uses special security credentials to sign HTTP requests. By consequence, you must first setup the following environment variables with the credentials you obtained while creating the bucket.

$ export AWS_ACCESS_KEY_ID=<MY_ACCESS_KEY>
$ export AWS_SECRET_ACCESS_KEY=<MY_SECRET_ACCESS_KEY>

When using temporary credentials make sure to include the session token via the environment variable AWS_SESSION_TOKEN.

You can then easily initialize a repository that uses your Amazon S3 as a backend. Make sure to use the endpoint for the correct region. The example uses us-east-1. If the bucket does not exist it will be created in that region:

$ restic -r s3:s3.us-east-1.amazonaws.com/bucket_name init
enter password for new repository:
enter password again:
created restic repository eefee03bbd at s3:s3.us-east-1.amazonaws.com/bucket_name
Please note that knowledge of your password is required to access the repository.
Losing your password means that your data is irrecoverably lost.

Until version 0.8.0, restic used a default prefix of restic, so the files in the bucket were placed in a directory named restic. If you want to access a repository created with an older version of restic, specify the path after the bucket name like this:

$ restic -r s3:s3.us-east-1.amazonaws.com/bucket_name/restic [...]

Note

restic expects path-style URLs like for example s3.us-west-2.amazonaws.com/bucket_name for Amazon S3. Virtual-hosted–style URLs like bucket_name.s3.us-west-2.amazonaws.com, where the bucket name is part of the hostname are not supported. These must be converted to path-style URLs instead, for example s3.us-west-2.amazonaws.com/bucket_name. See below for configuration options for S3-compatible storage from other providers.

Minio Server

Minio is an Open Source Object Storage, written in Go and compatible with Amazon S3 API.

• Download and Install Minio Download.

• You can also refer to Minio Docs for step by step guidance on installation and getting started on Minio Client and Minio Server.

You must first setup the following environment variables with the credentials of your Minio Server.

$ export AWS_ACCESS_KEY_ID=<YOUR-MINIO-ACCESS-KEY-ID>
$ export AWS_SECRET_ACCESS_KEY=<YOUR-MINIO-SECRET-ACCESS-KEY>

Now you can easily initialize restic to use Minio server as a backend with this command.

$ restic -r s3:http://localhost:9000/restic init
enter password for new repository:
enter password again:
created restic repository 6ad29560f5 at s3:http://localhost:9000/restic
Please note that knowledge of your password is required to access
the repository. Losing your password means that your data is irrecoverably lost.

S3-compatible Storage

For an S3-compatible server that is not Amazon, you can specify the URL to the server like this: s3:https://server:port/bucket_name.

If needed, you can manually specify the region to use by either setting the environment variable AWS_DEFAULT_REGION or calling restic with an option parameter like -o s3.region="us-east-1". If the region is not specified, the default region us-east-1 is used.

To select between path-style and virtual-hosted access, the extended option -o s3.bucket-lookup=auto can be used. It supports the following values:

• auto: Default behavior. Uses dns for Amazon and Google endpoints. Uses path for all other endpoints

• dns: Use virtual-hosted-style bucket access

• path: Use path-style bucket access

Certain S3-compatible servers do not properly implement the ListObjectsV2 API, most notably Ceph versions before v14.2.5. On these backends, as a temporary workaround, you can provide the -o s3.list-objects-v1=true option to use the older ListObjects API instead. This option may be removed in future versions of restic.

Wasabi

S3 storage from Wasabi can be used as follows.

• Determine the correct Wasabi service URL for your bucket here.

• Set environment variables with the necessary account credentials

$ export AWS_ACCESS_KEY_ID=<YOUR-WASABI-ACCESS-KEY-ID>
$ export AWS_SECRET_ACCESS_KEY=<YOUR-WASABI-SECRET-ACCESS-KEY>
$ restic -r s3:https://<WASABI-SERVICE-URL>/<WASABI-BUCKET-NAME> init

Alibaba Cloud (Aliyun) Object Storage System (OSS)

S3 storage from Alibaba OSS can be used as follows.

• Determine the correct Alibaba OSS region endpoint - this will be something like oss-eu-west-1.aliyuncs.com

• You will need the region name too - this will be something like oss-eu-west-1

• Set environment variables with the necessary account credentials

$ export AWS_ACCESS_KEY_ID=<YOUR-OSS-ACCESS-KEY-ID>
$ export AWS_SECRET_ACCESS_KEY=<YOUR-OSS-SECRET-ACCESS-KEY>
$ restic -o s3.bucket-lookup=dns -o s3.region=<OSS-REGION> -r s3:https://<OSS-ENDPOINT>/<OSS-BUCKET-NAME> init

OpenStack Swift

Restic can backup data to an OpenStack Swift container. Because Swift supports various authentication methods, credentials are passed through environment variables. In order to help integration with existing OpenStack installations, the naming convention of those variables follows the official Python Swift client:

# For keystone v1 authentication
$ export ST_AUTH=<MY_AUTH_URL>
$ export ST_USER=<MY_USER_NAME>
$ export ST_KEY=<MY_USER_PASSWORD>

# For keystone v2 authentication (some variables are optional)
$ export OS_AUTH_URL=<MY_AUTH_URL>
$ export OS_REGION_NAME=<MY_REGION_NAME>
$ export OS_USERNAME=<MY_USERNAME>
$ export OS_PASSWORD=<MY_PASSWORD>
$ export OS_TENANT_ID=<MY_TENANT_ID>
$ export OS_TENANT_NAME=<MY_TENANT_NAME>

# For keystone v3 authentication (some variables are optional)
$ export OS_AUTH_URL=<MY_AUTH_URL>
$ export OS_REGION_NAME=<MY_REGION_NAME>
$ export OS_USERNAME=<MY_USERNAME>
$ export OS_USER_ID=<MY_USER_ID>
$ export OS_PASSWORD=<MY_PASSWORD>
$ export OS_USER_DOMAIN_NAME=<MY_DOMAIN_NAME>
$ export OS_USER_DOMAIN_ID=<MY_DOMAIN_ID>
$ export OS_PROJECT_NAME=<MY_PROJECT_NAME>
$ export OS_PROJECT_DOMAIN_NAME=<MY_PROJECT_DOMAIN_NAME>
$ export OS_PROJECT_DOMAIN_ID=<MY_PROJECT_DOMAIN_ID>
$ export OS_TRUST_ID=<MY_TRUST_ID>

# For keystone v3 application credential authentication (application credential id)
$ export OS_AUTH_URL=<MY_AUTH_URL>
$ export OS_APPLICATION_CREDENTIAL_ID=<MY_APPLICATION_CREDENTIAL_ID>
$ export OS_APPLICATION_CREDENTIAL_SECRET=<MY_APPLICATION_CREDENTIAL_SECRET>

# For keystone v3 application credential authentication (application credential name)
$ export OS_AUTH_URL=<MY_AUTH_URL>
$ export OS_USERNAME=<MY_USERNAME>
$ export OS_USER_DOMAIN_NAME=<MY_DOMAIN_NAME>
$ export OS_APPLICATION_CREDENTIAL_NAME=<MY_APPLICATION_CREDENTIAL_NAME>
$ export OS_APPLICATION_CREDENTIAL_SECRET=<MY_APPLICATION_CREDENTIAL_SECRET>

# For authentication based on tokens
$ export OS_STORAGE_URL=<MY_STORAGE_URL>
$ export OS_AUTH_TOKEN=<MY_AUTH_TOKEN>

Restic should be compatible with an OpenStack RC file in most cases.

Once environment variables are set up, a new repository can be created. The name of the Swift container and optional path can be specified. If the container does not exist, it will be created automatically:

$ restic -r swift:container_name:/path init   # path is optional
enter password for new repository:
enter password again:
created restic repository eefee03bbd at swift:container_name:/path
Please note that knowledge of your password is required to access the repository.
Losing your password means that your data is irrecoverably lost.

The policy of the new container created by restic can be changed using environment variable:

$ export SWIFT_DEFAULT_CONTAINER_POLICY=<MY_CONTAINER_POLICY>

Backblaze B2

Warning

Due to issues with error handling in the current B2 library that restic uses, the recommended way to utilize Backblaze B2 is by using its S3-compatible API.

Follow the documentation to generate S3-compatible access keys and then setup restic as described at Amazon S3. This is expected to work better than using the Backblaze B2 backend directly.

Different from the B2 backend, restic’s S3 backend will only hide no longer necessary files. Thus, make sure to setup lifecycle rules to eventually delete hidden files. The lifecycle setting “Keep only the last version of the file” will keep only the most current version of a file. Read the [Backblaze documentation](https://www.backblaze.com/docs/cloud-storage-lifecycle-rules).

Restic can backup data to any Backblaze B2 bucket. You need to first setup the following environment variables with the credentials you can find in the dashboard on the “Buckets” page when signed into your B2 account:

$ export B2_ACCOUNT_ID=<MY_APPLICATION_KEY_ID>
$ export B2_ACCOUNT_KEY=<MY_APPLICATION_KEY>

To get application keys, a user can go to the App Keys section of the Backblaze account portal. You must create a master application key first. From there, you can generate a standard Application Key. Please note that the Application Key should be treated like a password and will only appear once. If an Application Key is forgotten, you must generate a new one.

For more information on application keys, refer to the Backblaze documentation.

Note

As of version 0.9.2, restic supports both master and non-master application keys. If using a non-master application key, ensure that it is created with at least read and write access to the B2 bucket. On earlier versions of restic, a master application key is required.

You can then initialize a repository stored at Backblaze B2. If the bucket does not exist yet and the credentials you passed to restic have the privilege to create buckets, it will be created automatically:

$ restic -r b2:bucketname:path/to/repo init
enter password for new repository:
enter password again:
created restic repository eefee03bbd at b2:bucketname:path/to/repo
Please note that knowledge of your password is required to access the repository.
Losing your password means that your data is irrecoverably lost.

Note that the bucket name must be unique across all of B2.

The number of concurrent connections to the B2 service can be set with the -o b2.connections=10 switch. By default, at most five parallel connections are established.

Microsoft Azure Blob Storage

You can also store backups on Microsoft Azure Blob Storage. Export the Azure Blob Storage account name:

$ export AZURE_ACCOUNT_NAME=<ACCOUNT_NAME>

For authentication export one of the following variables:

# For storage account key
$ export AZURE_ACCOUNT_KEY=<SECRET_KEY>
# For SAS
$ export AZURE_ACCOUNT_SAS=<SAS_TOKEN>

For authentication using az login ensure the user has the minimum permissions of the role assignment Storage Blob Data Contributor on Azure RBAC for the storage account.

$ az login

Alternatively, if run on Azure, restic will automatically use service accounts configured via the standard environment variables or Workload / Managed Identities.

To enforce the use of the Azure CLI credential when other credentials are present, set the following environment variable:

$ export AZURE_FORCE_CLI_CREDENTIAL=true

Restic will by default use Azure’s global domain core.windows.net as endpoint suffix. You can specify other suffixes as follows:

$ export AZURE_ENDPOINT_SUFFIX=<ENDPOINT_SUFFIX>

Afterwards you can initialize a repository in a container called foo in the root path like this:

$ restic -r azure:foo:/ init
enter password for new repository:
enter password again:

created restic repository a934bac191 at azure:foo:/
[...]

The number of concurrent connections to the Azure Blob Storage service can be set with the -o azure.connections=10 switch. By default, at most five parallel connections are established.

Google Cloud Storage

Note

Google Cloud Storage is not the same service as Google Drive - to use the latter, please see Other Services via rclone for instructions on using the rclone backend.

Restic supports Google Cloud Storage as a backend and connects via a service account.

For normal restic operation, the service account must have the storage.objects.{create,delete,get,list} permissions for the bucket. These are included in the “Storage Object Admin” role. restic init can create the repository bucket. Doing so requires the storage.buckets.create permission (“Storage Admin” role). If the bucket already exists, that permission is unnecessary.

To use the Google Cloud Storage backend, first create a service account key and download the JSON credentials file. Second, find the Google Project ID that you can see in the Google Cloud Platform console at the “Storage/Settings” menu. Export the path to the JSON key file and the project ID as follows:

$ export GOOGLE_PROJECT_ID=123123123123
$ export GOOGLE_APPLICATION_CREDENTIALS=$HOME/.config/gs-secret-restic-key.json

Restic uses Google’s client library to generate default authentication material, which means if you’re running in Google Container Engine or are otherwise located on an instance with default service accounts then these should work out of the box.

Alternatively, you can specify an existing access token directly:

$ export GOOGLE_ACCESS_TOKEN=ya29.a0AfH6SMC78...

If GOOGLE_ACCESS_TOKEN is set all other authentication mechanisms are disabled. The access token must have at least the https://www.googleapis.com/auth/devstorage.read_write scope. Keep in mind that access tokens are short-lived (usually one hour), so they are not suitable if creating a backup takes longer than that, for instance.

Once authenticated, you can use the gs: backend type to create a new repository in the bucket foo at the root path:

$ restic -r gs:foo:/ init
enter password for new repository:
enter password again:

created restic repository bde47d6254 at gs:foo/
[...]

The number of concurrent connections to the GCS service can be set with the -o gs.connections=10 switch. By default, at most five parallel connections are established.

The region, where a bucket should be created, can be specified with the -o gs.region=us switch. By default, the region is set to us.

Other Services via rclone

The program rclone can be used to access many other different services and store data there. First, you need to install and configure rclone. The general backend specification format is rclone:<remote>:<path>, the <remote>:<path> component will be directly passed to rclone. When you configure a remote named foo, you can then call restic as follows to initiate a new repository in the path bar in the remote foo:

$ restic -r rclone:foo:bar init

Restic takes care of starting and stopping rclone.

Note

If you get an error message saying “cannot implicitly run relative executable rclone found in current directory”, this means that an rclone executable was found in the current directory. For security reasons restic will not run this implicitly, instead you have to use the -o rclone.program=./rclone extended option to override this security check and explicitly tell restic to use the executable.

As a more concrete example, suppose you have configured a remote named b2prod for Backblaze B2 with rclone, with a bucket called yggdrasil. You can then use rclone to list files in the bucket like this:

$ rclone ls b2prod:yggdrasil

In order to create a new repository in the root directory of the bucket, call restic like this:

$ restic -r rclone:b2prod:yggdrasil init

If you want to use the path foo/bar/baz in the bucket instead, pass this to restic:

$ restic -r rclone:b2prod:yggdrasil/foo/bar/baz init

Listing the files of an empty repository directly with rclone should return a listing similar to the following:

$ rclone ls b2prod:yggdrasil/foo/bar/baz
    155 bar/baz/config
    448 bar/baz/keys/4bf9c78049de689d73a56ed0546f83b8416795295cda12ec7fb9465af3900b44

Rclone can be configured with environment variables, so for instance configuring a bandwidth limit for rclone can be achieved by setting the RCLONE_BWLIMIT environment variable:

$ export RCLONE_BWLIMIT=1M

For debugging rclone, you can set the environment variable RCLONE_VERBOSE=2.

The rclone backend has three additional options:

• -o rclone.program specifies the path to rclone, the default value is just rclone

• -o rclone.args allows setting the arguments passed to rclone, by default this is serve restic --stdio --b2-hard-delete

• -o rclone.timeout specifies timeout for waiting on repository opening, the default value is 1m

The reason for the --b2-hard-delete parameters can be found in the corresponding GitHub issue #1657.

In order to start rclone, restic will build a list of arguments by joining the following lists (in this order): rclone.program, rclone.args and as the last parameter the value that follows the rclone: prefix of the repository specification.

So, calling restic like this

$ restic -o rclone.program="/path/to/rclone" \
  -o rclone.args="serve restic --stdio --bwlimit 1M --b2-hard-delete --verbose" \
  -r rclone:b2:foo/bar

runs rclone as follows:

$ /path/to/rclone serve restic --stdio --bwlimit 1M --b2-hard-delete --verbose b2:foo/bar

Manually setting rclone.program also allows running a remote instance of rclone e.g. via SSH on a server, for example:

$ restic -o rclone.program="ssh user@remotehost rclone" -r rclone:b2:foo/bar

With these options, restic works with local files. It uses rclone and credentials stored on remotehost to communicate with B2. All data (except credentials) is encrypted/decrypted locally, then sent/received via remotehost to/from B2.

A more advanced version of this setup forbids specific hosts from removing files in a repository. See the blog post by Simon Ruderich for details and the documentation for the forget command to learn about important security considerations.

The rclone command may also be hard-coded in the SSH configuration or the user’s public key, in this case it may be sufficient to just start the SSH connection (and it’s irrelevant what’s passed after rclone: in the repository specification):

$ restic -o rclone.program="ssh user@host" -r rclone:x

Password prompt on Windows

At the moment, restic only supports the default Windows console interaction. If you use emulation environments like MSYS2 or Cygwin, which use terminals like Mintty or rxvt, you may get a password error.

You can workaround this by using a special tool called winpty (look here and here for detail information). On MSYS2, you can install winpty as follows:

$ pacman -S winpty
$ winpty restic -r /srv/restic-repo init

Group accessible repositories

Since restic version 0.14 local and SFTP repositories can be made accessible to members of a system group. To control this we have to change the group permissions of the top-level config file and restic will use this as a hint to determine what permissions to apply to newly created files. By default restic init sets repositories up to be group inaccessible.

In order to give group members read-only access we simply add the read permission bit to all repository files with chmod:

$ chmod -R g+r /srv/restic-repo

This serves two purposes: 1) it sets the read permission bit on the repository config file triggering restic’s logic to create new files as group accessible and 2) it actually allows the group read access to the files.

Note

By default files on Unix systems are created with a user’s primary group as defined by the gid (group id) field in /etc/passwd. See passwd(5).

For read-write access things are a bit more complicated. When users other than the repository creator add new files in the repository they will be group-owned by this user’s primary group by default, not that of the original repository owner, meaning the original creator wouldn’t have access to these files. That’s hardly what you’d want.

To make this work we can employ the help of the setgid permission bit available on Linux and most other Unix systems. This permission bit makes newly created directories inherit both the group owner (gid) and setgid bit from the parent directory. Setting this bit requires root but since it propagates down to any new directories we only have to do this privileged setup once:

# find /srv/restic-repo -type d -exec chmod g+s '{}' \;
$ chmod -R g+rw /srv/restic-repo

This sets the setgid bit on all existing directories in the repository and then grants read/write permissions for group access.

Note

To manage who has access to the repository you can use usermod on Linux systems, to change which group controls repository access chgrp -R is your friend.

Repositories with empty password

Restic by default refuses to create or operate on repositories that use an empty password. Since restic 0.17.0, the option --insecure-no-password allows disabling this check. Restic will not prompt for a password when using this option. Specifying --insecure-no-password while also passing a password to restic via a CLI option or via environment variable results in an error.

For security reasons, the option must always be specified when operating on repositories with an empty password. For example to create a new repository with an empty password, use the following command.

restic init --insecure-no-password

The init and copy command also support the option --from-insecure-no-password which applies to the source repository. The key add and key passwd commands include the --new-insecure-no-password option to add or set and empty password.