> For the complete documentation index, see [llms.txt](https://documentation.alluxio.io/os-cn/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://documentation.alluxio.io/os-cn/operation/admin-cli.md).

# 管理员命令行接口

Alluxio的管理员命令行接口为管理员提供了管理Alluxio文件系统的操作。 您可以调用以下命令行来获取所有子命令：

```console
$ ./bin/alluxio fsadmin
Usage: alluxio fsadmin [generic options]
       [report]
       [ufs --mode <noAccess/readOnly/readWrite> <ufsPath>]
       ...
```

以UFS URI作为参数的`fsadmin ufs`子命令，参数应该是像`hdfs://<name-service>/`这样的根UFS URI，而不是`hdfs://<name-service>/<folder>`。

## 操作列表

| 操作     | 语法                                                  | 描述                                                                         |
| ------ | --------------------------------------------------- | -------------------------------------------------------------------------- |
| backup | backup \[directory] \[--local]                      | Back up all Alluxio metadata to the backup directory configured on master. |
| doctor | doctor \[category]                                  | Show Alluxio errors and warnings.                                          |
| report | report \[category] \[category args]                 | Report Alluxio running cluster information.                                |
| ufs    | ufs --mode \<noAccess/readOnly/readWrite> "ufsPath" | Update attributes for a mounted under storage system.                      |

## 示例用例

### backup(备份)

`backup`命令创建Alluxio元数据的备份

备份到默认备份文件夹（由`alluxio.master.backup.directory`）配置

```
./bin/alluxio fsadmin backup
Successfully backed up journal to hdfs://mycluster/opt/alluxio/backups/alluxio-backup-2018-5-29-1527644810.gz
```

备份到下存储中的特定目录。

```
./bin/alluxio fsadmin backup /alluxio/special_backups
Successfully backed up journal to hdfs://mycluster/opt/alluxio/backups/alluxio-backup-2018-5-29-1527644810.gz
```

备份到主主机的本地文件系统的特定目录。

```
./bin/alluxio fsadmin backup /opt/alluxio/backups/ --local
Successfully backed up journal to file:///opt/alluxio/backups/alluxio-backup-2018-5-29-1527644810.gz on master Master2
```

### doctor

`doctor`命令显示Alluxio错误和警告。

```console
# shows server-side configuration errors and warnings
$ ./bin/alluxio fsadmin doctor configuration
```

### report

`report`命令提供了Alluxio运行中的集群信息。

```console
# Report cluster summary
$ ./bin/alluxio fsadmin report

# Report worker capacity information
$ ./bin/alluxio fsadmin report capacity

# Report runtime configuration information 
$ ./bin/alluxio fsadmin report configuration

# Report metrics information
$ ./bin/alluxio fsadmin report metrics

# Report under file system information
$ ./bin/alluxio fsadmin report ufs
```

使用 `-h` 选项来获得更多信息。

### ufs

`ufs`命令提供了选项来更新挂载的底层存储的属性。`mode`选项可用于将底层存储设置为维护模式。目前某些操作可能会受到限制。

例如，一个底层存储可以设为`readOnly`模式来禁止写入操作。 Alluxio将不会对底层存储尝试任何写入操作。

```console
$ ./bin/alluxio fsadmin ufs --mode readOnly hdfs://ns
```

`fsadmin ufs`命令接受一个UFS URI作为参数。该参数需要是一个 UFS URI的根，类似`hdfs://<name-service>/`，而非`hdfs://<name-service>/<folder>`。


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://documentation.alluxio.io/os-cn/operation/admin-cli.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.