Ceph分布式存储实践应用之集群测试验证（Rados运用）-原创手记-慕课网

1. 创建Cephfs

集群创建完后，默认没有文件系统，要是实现文件的存储操作，我们还需创建一个Cephfs可以支持对外访问的文件系统。

创建两个存储池, 执行两条命令：
```
ceph osd pool create cephfs_data 128
ceph osd pool create cephfs_metadata 64
```
少于5个OSD可把pg_num设置为128

OSD数量在5到10，可以设置pg_num为512

OSD数量在10到50，可以设置pg_num为4096

OSD数量大于50，需要计算pg_num的值

通过下面命令可以列出当前创建的存储池：
```
ceph osd lspools
```

创建fs, 名称为fs_test:

ceph fs new fs_test cephfs_metadata cephfs_data

状态查看，以下信息代表正常：

[root@CENTOS7-1 mgr-dashboard]# ceph fs ls
name: fs_test, metadata pool: cephfs_metadata, data pools: [cephfs_data ]

[root@CENTOS7-1 mgr-dashboard]# ceph mds stat
fs_test-1/1/1 up  {0=centos7-1=up:active}

附：如果创建错误，需要删除，执行：

ceph fs rm fs_test --yes-i-really-mean-it
ceph osd pool delete cephfs_data cephfs_data  --yes-i-really-really-mean-it

确保在ceph.conf中开启以下配置：

[mon]
mon allow pool delete = true

采用fuse挂载

先确定ceph-fuse命令能执行，如果没有，则安装：
```
 yum -y install ceph-fuse
```
创建挂载目录
```
mkdir -p /usr/local/cephfs_directory
```

挂载cephfs

[root@node3 ~]# ceph-fuse -k /etc/ceph/ceph.client.admin.keyring -m 10.10.20.11:6789 /usr/local/cephfs_directory
ceph-fuse[6687]: starting ceph client
2019-07-14 21:39:09.644181 7fa5be56e040 -1 init, newargv = 0x7fa5c940b500 newargc=9
ceph-fuse[6687]: starting fuse

查看磁盘挂载信息

[root@CENTOS7-1 mgr-dashboard]# df -h
Filesystem               Size  Used Avail Use% Mounted on
/dev/mapper/centos-root   38G  3.0G   35G   8% /
devtmpfs                 1.9G     0  1.9G   0% /dev
tmpfs                    1.9G     0  1.9G   0% /dev/shm
tmpfs                    1.9G   20M  1.9G   2% /run
tmpfs                    1.9G     0  1.9G   0% /sys/fs/cgroup
/dev/sda1                197M  167M   31M  85% /boot
tmpfs                    378M     0  378M   0% /run/user/0
tmpfs                    1.9G   24K  1.9G   1% /var/lib/ceph/osd/ceph-0
ceph-fuse                 27G     0   27G   0% /usr/local/cephfs_directory
tmpfs                    378M     0  378M   0% /run/user/1000

/usr/local/cephfs_directory目录已成功挂载。

2. 客户端连接验证(Rados Java)

安装好JDK、GIT和MAVEN。
下载rados java客户端源码

git clone https://github.com/ceph/rados-java.git

下载目录位置：
```
[root@CENTOS7-1 rados-java]# pwd
/usr/local/sources/rados-java
```

执行MAVEN安装, 忽略测试用例：

[root@CENTOS7-1 rados-java]# mvn install -Dmaven.test.skip=true

生成jar包， rados-0.6.0-SNAPSHOT.jar

[root@CENTOS7-1 target]# ll
total 104
drwxr-xr-x 3 root root     17 Jul 14 19:31 classes
drwxr-xr-x 2 root root     27 Jul 14 19:31 dependencies
drwxr-xr-x 3 root root     25 Jul 14 19:31 generated-sources
drwxr-xr-x 2 root root     28 Jul 14 19:31 maven-archiver
drwxr-xr-x 3 root root     35 Jul 14 19:31 maven-status
-rw-r--r-- 1 root root 105570 Jul 14 19:31 rados-0.6.0-SNAPSHOT.jar

创建软链接，加入CLASSPATH

ln -s /usr/local/sources/rados-java/target/rados-0.6.0-SNAPSHOT.jar /usr/local/jdk1.8.0_181/jre/lib/ext/rados-0.6.0-SNAPSHOT.jar

安装jna

yum -y install jna

创建软链接

ln -s /usr/share/java/jna.jar /usr/local/jdk1.8.0_181/jre/lib/ext/jna.jar

查看

[root@CENTOS7-1 target]# ll /usr/local/jdk1.8.0_181/jre/lib/ext/jna.jar 
lrwxrwxrwx 1 root root 23 Jul 14 10:23 /usr/local/jdk1.8.0_181/jre/lib/ext/jna.jar -> /usr/share/java/jna.jar

[root@CENTOS7-1 target]# ll /usr/local/jdk1.8.0_181/jre/lib/ext/rados-0.6.0-SNAPSHOT.jar 
lrwxrwxrwx 1 root root 40 Jul 14 10:25 /usr/local/jdk1.8.0_181/jre/lib/ext/rados-0.6.0-SNAPSHOT.jar -> /usr/share/java/rados-0.6.0-SNAPSHOT.jar

创建JAVA测试类

CephClient类，注意，最新版0.6的异常处理包位置已发生变化。

import com.ceph.rados.Rados;
import com.ceph.rados.exceptions.*;

import java.io.File;

public class CephClient {
        public static void main (String args[]){

                try {
                        Rados cluster = new Rados("admin");
                        System.out.println("Created cluster handle.");

                        File f = new File("/etc/ceph/ceph.conf");
                        cluster.confReadFile(f);
                        System.out.println("Read the configuration file.");

                        cluster.connect();
                        System.out.println("Connected to the cluster.");

                } catch (RadosException e) {
                        System.out.println(e.getMessage() + ": " + e.getReturnValue());
                }
        }
}

运行验证

需要在linux环境下运行，且要在client节点。

编译并运行：

[root@CENTOS7-1 sources]# javac CephClient.java 
[root@CENTOS7-1 sources]# java CephClient
Created cluster handle.
Read the configuration file.
Connected to the cluster.

成功与ceph建立连接。

3. Ceph与项目集成使用

工程设计

演示经常使用的文件上传与下载功能，看java是如何在项目中使用。
工程结构

创建一个Spring Boot工程，创建一个是启动类和一个ceph操作封装类。

工程实现

CephDemoApplication启动类：

@SpringBootApplication
public class CephDemoApplication {

    public static void main(String[] args) {

        System.out.println("start....");
        String username = "admin";
        String monIp = "10.10.20.11:6789;10.10.20.12:6789;10.10.20.13:6789";
        String userKey = "AQBZBypdMchvBRAAbWVnIGyYNvxWQZ2UkuiYew==";
        String mountPath = "/";
        CephOperator cephOperate = null;
        try {
            String opt = (args == null || args.length < 1)? "" : args[0];
            cephOperate = new CephOperator(username, monIp, userKey, mountPath);
            if("upload".equals(opt)) {
                cephOperate.uploadFileByPath("/temp_upload_fs", args[1]);
            }else if("download".equals(opt)) {
                cephOperate.downloadFileByPath("/temp_download_fs", args[1]);
            }else {
                System.out.println("Unrecognized Command! Usage  opt[upload|download] filename[path]!");
            }
        }catch(Exception e) {
            e.printStackTrace();
        }finally {
            if(null != cephOperate) {
                cephOperate.umount();
            }
        }
        System.out.println("end....");

    }

}

monIp为ceph client节点连接地址与端口，支持多个；

userKey为密钥，对应ceph.client.admin.keyring中的key值。

启动接收两个参数，一个是标识上传或下载，另一个是标识文件名称。

CephOperator操作类的实现：

public class CephOperator {

    private CephMount mount;
    private String username;
    private String monIp;
    private String userKey;

    public CephOperator(String username, String monIp, String userKey, String mountPath) {
        this.username = username;
        this.monIp = monIp;
        this.userKey = userKey;
        this.mount = new CephMount(username);
        this.mount.conf_set("mon_host", monIp);
        mount.conf_set("key", userKey);
        mount.mount(mountPath);
    }

    //查看目录列表
    public void listDir(String path) throws IOException {
        String[] dirs = mount.listdir(path);
        System.out.println("contents of the dir: " + Arrays.asList(dirs));
    }

    //新建目录
    public void mkDir(String path) throws IOException {
        mount.mkdirs(path, 0755);//0表示十进制
    }

    //删除目录
    public void delDir(String path) throws IOException {
        mount.rmdir(path);
    }

    //重命名目录or文件
    public void renameDir(String oldName, String newName) throws IOException {
        mount.rename(oldName, newName);
    }

    //删除文件
    public void delFile(String path) throws IOException {
        mount.unlink(path);
    }

    /**
     * 上传指定路径文件
     * @param filePath
     * @param fileName
     * @return
     */
    public Boolean uploadFileByPath(String filePath, String fileName) {

        // 如果mount操作单元为空则直接返回
        if (this.mount == null) {
            return null;
        }
        // 文件描述信息定义
        char pathChar = File.separatorChar;
        String fileFullName = "";
        Long fileLength = 0l;
        Long uploadedLength = 0l;
        File file = null;

        // 定义文件流
        FileInputStream fis = null;

        // 获取本地文件信息
        fileFullName = filePath + pathChar + fileName;
        file = new File(fileFullName);
        if (!file.exists()) {
            return false;
        }
        fileLength = file.length();

        // 获取本地文件流
        try {
            fis = new FileInputStream(file);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }

        // 判断文件是否已经存在
        String[] dirList = null;
        Boolean fileExist = false;
        try {
            dirList = this.mount.listdir("/");
            for (String fileInfo : dirList) {
                if (fileInfo.equals(fileName)) {
                    fileExist = true;
                }
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }

        if (!fileExist) {
            try {
                // 创建文件并设置为写入模式
                this.mount.open(fileName, CephMount.O_CREAT, 0);
                int fd = this.mount.open(fileName, CephMount.O_RDWR, 0);

                // 开始文件传输
                int length = 0;
                byte[] bytes = new byte[1024];
                while ((length = fis.read(bytes, 0, bytes.length)) != -1) {
                    // 上传写入数据
                    this.mount.write(fd, bytes, length, uploadedLength); 

                    // 更新上传进度
                    uploadedLength += length;

                    // 输出上传百分比
                    float rate = (float) uploadedLength * 100 / (float) fileLength;
                    String rateValue = (int) rate + "%";
                    System.out.println(rateValue);

                    // 上传完成后退出
                    if (uploadedLength == fileLength) {
                        break;
                    }
                }
                System.out.println("文件传输成功！");

                // 设置文件权限
                this.mount.fchmod(fd, 0666);

                // 关闭操作
                this.mount.close(fd);
                if (fis != null) {
                    fis.close();
                }
                return true;
            } catch (Exception e) {
                e.printStackTrace();
            }
        } else if (fileExist) {
            try {
                // 获取文件大小
                CephStat stat = new CephStat();
                this.mount.stat(fileName, stat);
                long lastLen= stat.size;
                int fd = this.mount.open(fileName, CephMount.O_RDWR, 0);

                // 开始文件传输
                int length = 0;
                byte[] bytes = new byte[1024];
                long uploadActLen= 0;
                while ((length = fis.read(bytes, 0, bytes.length)) != -1) {
                    // 更新写入
                    this.mount.write(fd, bytes, length, lastLen);

                    // 更新文件大小
                    uploadActLen += length;
                    // 更新文件上传百分比
                    float rate = (float) uploadActLen * 100 / (float) fileLength;
                    String rateValue = (int) rate + "%";
                    System.out.println(rateValue);

                    // complete flag
                    if (uploadActLen == fileLength) {
                        break;
                    }
                }
                // 多次上传会进行追加
                System.out.println("追加文件传输成功！");

                // 设置文件权限
                this.mount.fchmod(fd, 0666);

                // 关闭操作
                this.mount.close(fd);
                if (fis != null) {
                    fis.close();
                }
                return true;
            } catch (Exception e) {
                e.printStackTrace();
            }
        } else {
            try {
                if (fis != null) {
                    fis.close();
                }
            } catch (Exception e) {
                e.printStackTrace();
            }
            return false;
        }

        return false;
    }

    // 设置当前的工作上传目录
    public void setWorkDir(String path) throws IOException {
        mount.chdir(path);
    }
 
    //外部获取mount
    public CephMount getMount() {
        return this.mount;
    }

    // 取消文件挂载
    public void umount() {
        mount.unmount();
    }
   
    /**
     * 下载文件到指定路径
     * @param filePath
     * @param fileName
     * @return
     */
    public Boolean downloadFileByPath(String filePath, String fileName) {

        // 如果mount操作单元为空则直接返回
        if (this.mount == null) {
            return null;
        }

        // 文件描述信息定义
        char pathChar = File.separatorChar;
        String fileFullName = "";
        Long fileLength = 0l;
        Long downloadedLength = 0l;
        File file = null;

        // 定义文件流
        FileOutputStream fos = null;
        RandomAccessFile raf = null;

        // 创建新的文件
        fileFullName = filePath + pathChar + fileName;
        file = new File(fileFullName);

        // 获取 cephfs 的文件大小
        try {
            CephStat stat = new CephStat();
            this.mount.stat(fileName, stat);
            fileLength = stat.size;
        } catch (Exception e) {
            e.printStackTrace();
        }

        if (fileLength != 0) {
            if (!file.exists()) {
                // 下载文件
                int length = 10240;
                byte[] bytes = new byte[length];
                try {
                    int fd = this.mount.open(fileName, CephMount.O_RDONLY, 0);
                    fos = new FileOutputStream(file);
                    float rate = 0;
                    String rateValue = "";
                    while ((fileLength - downloadedLength) >= length && (this.mount.read(fd, bytes, (long) length, downloadedLength)) != -1) {
                        fos.write(bytes, 0, length);
                        fos.flush();
                        downloadedLength += (long) length;

                        // 输出进度百分比
                        rate = (float) downloadedLength * 100 / (float) fileLength;
                        rateValue = (int) rate + "%";
                        System.out.println(rateValue);

                        if (downloadedLength == fileLength) {
                            break;
                        }
                    }
                    if (downloadedLength != fileLength) {
                        this.mount.read(fd, bytes, fileLength - downloadedLength, downloadedLength);
                        fos.write(bytes, 0, (int) (fileLength - downloadedLength));
                        fos.flush();
                        downloadedLength = fileLength;

                        // 输出进度百分比
                        rate = (float) downloadedLength * 100 / (float) fileLength;
                        rateValue = (int) rate + "%";
                        System.out.println(rateValue);
                    }

                    System.out.println("Download Success!");
                    fos.close();
                    this.mount.close(fd);
                    return true;
                } catch (Exception e) {
                    e.printStackTrace();
                }
            } else if (file.exists()) {
                // 下载文件
                int length = 10240;
                byte[] bytes = new byte[length];
                Long filePoint = file.length();
                try {
                    int fd = this.mount.open(fileName, CephMount.O_RDONLY, 0);
                    raf = new RandomAccessFile(file, "rw");
                    raf.seek(filePoint);
                    downloadedLength = filePoint;
                    float rate = 0;
                    String rateValue = "";
                    while ((fileLength - downloadedLength) >= length && (this.mount.read(fd, bytes, (long) length, downloadedLength)) != -1) {
                        raf.write(bytes, 0, length);
                        downloadedLength += (long) length;

                        // 输出进度百分比
                        rate = (float) downloadedLength * 100 / (float) fileLength;
                        rateValue = (int) rate + "%";
                        System.out.println(rateValue);

                        if (downloadedLength == fileLength) {
                            break;
                        }
                    }
                    if (downloadedLength != fileLength) {
                        this.mount.read(fd, bytes, fileLength - downloadedLength, downloadedLength);
                        raf.write(bytes, 0, (int) (fileLength - downloadedLength));
                        downloadedLength = fileLength;

                        // 输出进度百分比
                        rate = (float) downloadedLength * 100 / (float) fileLength;
                        rateValue = (int) rate + "%";
                        System.out.println(rateValue);
                    }
					// 如果下载中断, 会从上一次下载结束位置进行上传
                    System.out.println("Cut Point Download Success!");
                    raf.close();
                    this.mount.close(fd);
                    return true;
                } catch (Exception e) {
                    e.printStackTrace();
                }
            } else {
                return false;
            }
        }else {
            System.out.println(" the file is empty!");
        } 
        return true;   
    }   
}

POM文件配置：

<dependencies>
    <!-- Spring Boot 依赖-->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>

    <!-- Rados Java Api依赖 -->
    <dependency>
        <groupId>com.ceph</groupId>
        <artifactId>rados</artifactId>
        <version>0.6.0</version>
    </dependency>
	<!-- Cephfs 文件系统依赖 -->
    <dependency>
        <groupId>com.ceph</groupId>
        <artifactId>libcephfs</artifactId>
        <version>0.80.5</version>
    </dependency>
</dependencies>

<!--Spring Boot 打包插件 -->
<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
    </plugins>
</build>

测试验证

通过maven 命令 clean install 打包生成jar文件。

rz命令上传至client node服务器

[root@CENTOS7-1 sources]# ll ceph-demo.jar 
-rw-r--r-- 1 root root 16915296 Jul 14  2019 ceph-demo.jar

代码中的上传目录为/temp_upload_fs，创建名为upload.txt的文件，内容为abc123
```
[root@CENTOS7-1 sources]# cat /temp_upload_fs/upload.txt
abc123
```

上传至cephfs服务

[root@CENTOS7-1 sources]# java -jar ceph-demo.jar upload upload.txt
start....
100%
文件传输成功！
end....

下载cephfs文件

文件名称为上传时创建的upload.txt

[root@CENTOS7-1 sources]# java -jar ceph-demo.jar download upload.txt
start....
100%
Download Success!
end....

查看下载内容

[root@CENTOS7-1 sources]# cat /temp_download_fs/upload.txt 
abc123

通过演示，可以看到能够通过java client 在项目中成功操作ceph。

![file](//img1.sycdn.imooc.com/606c3df20001047f07330472.png)

FAQ问题

如果运行过程当中出现jni找不到动态库，需要安装相关依赖：

yum -y install libcephfs2 libcephfs_jni-devel

并检查相应的软链接：

[root@CENTOS7-1 sources]# ll /usr/lib/libcephfs_jni.so.2 
lrwxrwxrwx 1 root root 25 Jul 14 11:34 /usr/lib/libcephfs_jni.so.2 -> /usr/lib64/libcephfs.so.2

如果rados版本0.6.0依赖，需要手工上传至MAVEN仓库，命令：

mvn deploy:deploy-file -DgroupId=com.ceph -DartifactId=rados -Dversion=2.0.1 -Dpackaging=jar -Dfile=d:/TestCode/rados-0.6.0-SNAPSHOT.jar -url=http://192.168.19.102:8082/repository/maven-releases/ -DrepositoryId=nexus-releases