VictoriaMetrics/app/vmrestore/README.md

## vmrestore

`vmrestore` restores data from backups created by [vmbackup](https://victoriametrics.github.io/vbackup.html).
VictoriaMetrics `v1.29.0` and newer versions must be used for working with the restored data.

Restore process can be interrupted at any time. It is automatically resumed from the interruption point
when restarting `vmrestore` with the same args.


### Usage

VictoriaMetrics must be stopped during the restore process.

```
vmrestore -src=gcs://<bucket>/<path/to/backup> -storageDataPath=<local/path/to/restore>

```

* `<bucket>` is [GCS bucket](https://cloud.google.com/storage/docs/creating-buckets) name.
* `<path/to/backup>` is the path to backup made with [vmbackup](https://victoriametrics.github.io/vbackup.html) on GCS bucket.
* `<local/path/to/restore>` is the path to folder where data will be restored. This folder must be passed
  to VictoriaMetrics in `-storageDataPath` command-line flag after the restore process is complete.

The original `-storageDataPath` directory may contain old files. They will be substituted by the files from backup,
i.e. the end result would be similar to [rsync --delete](https://askubuntu.com/questions/476041/how-do-i-make-rsync-delete-files-that-have-been-deleted-from-the-source-folder).


### Troubleshooting

* If `vmrestore` eats all the network bandwidth, then set `-maxBytesPerSecond` to the desired value.
* If `vmrestore` has been interrupted due to temporary error, then just restart it with the same args. It will resume the restore process.


### Advanced usage

* Obtaining credentials from a file.

  Add flag `-credsFilePath=/etc/credentials` with following content:

    for s3 (aws, minio or other s3 compatible storages):
     ```bash
     [default]
     aws_access_key_id=theaccesskey
     aws_secret_access_key=thesecretaccesskeyvalue
    ```

    for gce cloud storage:
    ```json
    {
           "type": "service_account",
           "project_id": "project-id",
           "private_key_id": "key-id",
           "private_key": "-----BEGIN PRIVATE KEY-----\nprivate-key\n-----END PRIVATE KEY-----\n",
           "client_email": "service-account-email",
           "client_id": "client-id",
           "auth_uri": "https://accounts.google.com/o/oauth2/auth",
           "token_uri": "https://accounts.google.com/o/oauth2/token",
           "auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
           "client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/service-account-email"
    }
    ```

* Usage with s3 custom url endpoint.  It is possible to use `vmrestore` with s3 api compatible storages, like  minio, cloudian and other.
  You have to add custom url endpoint with a flag:
```
  # for minio:
  -customS3Endpoint=http://localhost:9000

  # for aws gov region
  -customS3Endpoint=https://s3-fips.us-gov-west-1.amazonaws.com
```

*  Run `vmrestore -help` in order to see all the available options:

```
  -concurrency int
    	The number of concurrent workers. Higher concurrency may reduce restore duration (default 10)
  -configFilePath string
    	Path to file with S3 configs. Configs are loaded from default location if not set.
    	See https://docs.aws.amazon.com/general/latest/gr/aws-security-credentials.html
  -configProfile string
    	Profile name for S3 configs. If no set, the value of the environment variable will be loaded (AWS_PROFILE or AWS_DEFAULT_PROFILE), or if both not set, DefaultSharedConfigProfile is used
  -credsFilePath string
    	Path to file with GCS or S3 credentials. Credentials are loaded from default locations if not set.
    	See https://cloud.google.com/iam/docs/creating-managing-service-account-keys and https://docs.aws.amazon.com/general/latest/gr/aws-security-credentials.html
  -customS3Endpoint string
    	Custom S3 endpoint for use with S3-compatible storages (e.g. MinIO). S3 is used if not set
  -envflag.enable
    	Whether to enable reading flags from environment variables additionally to command line. Command line flag values have priority over values from environment vars. Flags are read only from command line if this flag isn't set
  -envflag.prefix string
    	Prefix for environment variables if -envflag.enable is set
  -fs.disableMmap
    	Whether to use pread() instead of mmap() for reading data files. By default mmap() is used for 64-bit arches and pread() is used for 32-bit arches, since they cannot read data files bigger than 2^32 bytes in memory. mmap() is usually faster for reading small data chunks than pread()
  -loggerErrorsPerSecondLimit int
    	Per-second limit on the number of ERROR messages. If more than the given number of errors are emitted per second, then the remaining errors are suppressed. Zero value disables the rate limit (default 10)
  -loggerFormat string
    	Format for logs. Possible values: default, json (default "default")
  -loggerLevel string
    	Minimum level of errors to log. Possible values: INFO, WARN, ERROR, FATAL, PANIC (default "INFO")
  -loggerOutput string
    	Output for the logs. Supported values: stderr, stdout (default "stderr")
  -maxBytesPerSecond value
    	The maximum download speed. There is no limit if it is set to 0
    	Supports the following optional suffixes for values: KB, MB, GB, KiB, MiB, GiB (default 0)
  -memory.allowedBytes value
    	Allowed size of system memory VictoriaMetrics caches may occupy. This option overrides -memory.allowedPercent if set to non-zero value. Too low value may increase cache miss rate, which usually results in higher CPU and disk IO usage. Too high value may evict too much data from OS page cache, which will result in higher disk IO usage
    	Supports the following optional suffixes for values: KB, MB, GB, KiB, MiB, GiB (default 0)
  -memory.allowedPercent float
    	Allowed percent of system memory VictoriaMetrics caches may occupy. See also -memory.allowedBytes. Too low value may increase cache miss rate, which usually results in higher CPU and disk IO usage. Too high value may evict too much data from OS page cache, which will result in higher disk IO usage (default 60)
  -skipBackupCompleteCheck
    	Whether to skip checking for 'backup complete' file in -src. This may be useful for restoring from old backups, which were created without 'backup complete' file
  -src string
    	Source path with backup on the remote storage. Example: gcs://bucket/path/to/backup/dir, s3://bucket/path/to/backup/dir or fs:///path/to/local/backup/dir
  -storageDataPath string
    	Destination path where backup must be restored. VictoriaMetrics must be stopped when restoring from backup. -storageDataPath dir can be non-empty. In this case the contents of -storageDataPath dir is synchronized with -src contents, i.e. it works like 'rsync --delete' (default "victoria-metrics-data")
  -version
    	Show VictoriaMetrics version
```


### How to build from sources

It is recommended using [binary releases](https://github.com/VictoriaMetrics/VictoriaMetrics/releases) - see `vmutils-*` archives there.


#### Development build

1. [Install Go](https://golang.org/doc/install). The minimum supported version is Go 1.13.
2. Run `make vmrestore` from the root folder of the repository.
   It builds `vmrestore` binary and puts it into the `bin` folder.

#### Production build

1. [Install docker](https://docs.docker.com/install/).
2. Run `make vmrestore-prod` from the root folder of the repository.
   It builds `vmrestore-prod` binary and puts it into the `bin` folder.

#### Building docker images

Run `make package-vmrestore`. It builds `victoriametrics/vmrestore:<PKG_TAG>` docker image locally.
`<PKG_TAG>` is auto-generated image tag, which depends on source code in the repository.
The `<PKG_TAG>` may be manually set via `PKG_TAG=foobar make package-vmrestore`.

The base docker image is [alpine](https://hub.docker.com/_/alpine) but it is possible to use any other base image
by setting it via `<ROOT_IMAGE>` environment variable. For example, the following command builds the image on top of [scratch](https://hub.docker.com/_/scratch) image:

```bash
ROOT_IMAGE=scratch make package-vmrestore
```