Checkpoint is a fault-tolerant recovery mechanism. This mechanism ensures that when the program is running, it can recover itself even if it suddenly encounters an exception.
Checkpoint Storage is a storage mechanism for storing checkpoint data.
SeaTunnel Engine supports the following checkpoint storage types:
We use the microkernel design pattern to separate the checkpoint storage module from the engine. This allows users to implement their own checkpoint storage modules.
checkpoint-storage-api is the checkpoint storage module API, which defines the interface of the checkpoint storage module.
If you want to implement your own checkpoint storage module, you need to implement the CheckpointStorage and provide the corresponding CheckpointStorageFactory implementation.
The configuration of the seatunnel-server module is in the seatunnel.yaml file.
seatunnel: engine: checkpoint: storage: type: hdfs #plugin name of checkpoint storage, we support hdfs(S3, local, hdfs), localfile (native local file) is the default, but this plugin is de # plugin configuration plugin-config: namespace: #checkpoint storage parent path, the default value is /seatunnel/checkpoint/ K1: V1 # plugin other configuration K2: V2 # plugin other configuration
Notice: namespace must end with “/”.
Aliyun OSS based hdfs-file you can refer Hadoop OSS Docs to config oss.
Except when interacting with oss buckets, the oss client needs the credentials needed to interact with buckets. The client supports multiple authentication mechanisms and can be configured as to which mechanisms to use, and their order of use. Custom implementations of org.apache.hadoop.fs.aliyun.oss.AliyunCredentialsProvider may also be used. If you used AliyunCredentialsProvider (can be obtained from the Aliyun Access Key Management), these consist of an access key, a secret key. You can config like this:
seatunnel: engine: checkpoint: interval: 6000 timeout: 7000 storage: type: hdfs max-retained: 3 plugin-config: storage.type: oss oss.bucket: your-bucket fs.oss.accessKeyId: your-access-key fs.oss.accessKeySecret: your-secret-key fs.oss.endpoint: endpoint address
For additional reading on the Hadoop Credential Provider API, you can see: Credential Provider API.
For Aliyun OSS Credential Provider implements, you can see: Auth Credential Providers
Tencent COS based hdfs-file you can refer Hadoop COS Docs to config COS.
Except when interacting with cos buckets, the cos client needs the credentials needed to interact with buckets. The client supports multiple authentication mechanisms and can be configured as to which mechanisms to use, and their order of use. Custom implementations of com.qcloud.cos.auth.COSCredentialsProvider may also be used. If you used SimpleCredentialsProvider (can be obtained from the Tencent Cloud API Key Management), these consist of an access key, a secret key. You can config like this:
seatunnel: engine: checkpoint: interval: 6000 timeout: 7000 storage: type: hdfs max-retained: 3 plugin-config: storage.type: cos cos.bucket: cosn://your-bucket fs.cosn.credentials.provider: org.apache.hadoop.fs.cosn.auth.SimpleCredentialsProvider fs.cosn.userinfo.secretId: your-secretId fs.cosn.userinfo.secretKey: your-secretKey fs.cosn.bucket.region: your-region
For additional reading on the Hadoop Credential Provider API, you can see: Credential Provider API.
For additional COS configuration, you can see: Tencent Hadoop-COS Docs
Please add the following jar to the lib directory:
S3 based hdfs-file you can refer hadoop s3 docs to config s3.
Except when interacting with public S3 buckets, the S3A client needs the credentials needed to interact with buckets. The client supports multiple authentication mechanisms and can be configured as to which mechanisms to use, and their order of use. Custom implementations of com.amazonaws.auth.AWSCredentialsProvider may also be used. If you used SimpleAWSCredentialsProvider (can be obtained from the Amazon Security Token Service), these consist of an access key, a secret key. You can config like this:
seatunnel: engine: checkpoint: interval: 6000 timeout: 7000 storage: type: hdfs max-retained: 3 plugin-config: storage.type: s3 s3.bucket: your-bucket fs.s3a.access.key: your-access-key fs.s3a.secret.key: your-secret-key fs.s3a.aws.credentials.provider: org.apache.hadoop.fs.s3a.SimpleAWSCredentialsProvider
If you used InstanceProfileCredentialsProvider, which supports use of instance profile credentials if running in an EC2 VM, you can check iam-roles-for-amazon-ec2. You can config like this:
seatunnel: engine: checkpoint: interval: 6000 timeout: 7000 storage: type: hdfs max-retained: 3 plugin-config: storage.type: s3 s3.bucket: your-bucket fs.s3a.endpoint: your-endpoint fs.s3a.aws.credentials.provider: org.apache.hadoop.fs.s3a.InstanceProfileCredentialsProvider
If you want to use Minio that supports the S3 protocol as checkpoint storage, you should configure it this way:
seatunnel: engine: checkpoint: interval: 10000 timeout: 60000 storage: type: hdfs max-retained: 3 plugin-config: storage.type: s3 fs.s3a.access.key: xxxxxxxxx # Access Key of MinIO fs.s3a.secret.key: xxxxxxxxxxxxxxxxxxxxx # Secret Key of MinIO fs.s3a.endpoint: http://127.0.0.1:9000 # Minio HTTP service access address s3.bucket: s3a://test # test is the bucket name which storage the checkpoint file fs.s3a.aws.credentials.provider: org.apache.hadoop.fs.s3a.SimpleAWSCredentialsProvider # important: The user of this key needs to have write permission for the bucket, otherwise an exception of 403 will be returned
For additional reading on the Hadoop Credential Provider API, you can see: Credential Provider API.
if you use HDFS, you can config like this:
seatunnel: engine: checkpoint: storage: type: hdfs max-retained: 3 plugin-config: storage.type: hdfs fs.defaultFS: hdfs://localhost:9000 // if you used kerberos, you can config like this: kerberosPrincipal: your-kerberos-principal kerberosKeytabFilePath: your-kerberos-keytab // if you need hdfs-site config, you can config like this: hdfs_site_path: /path/to/your/hdfs_site_path
if HDFS is in HA mode , you can config like this:
seatunnel: engine: checkpoint: storage: type: hdfs max-retained: 3 plugin-config: storage.type: hdfs fs.defaultFS: hdfs://usdp-bing seatunnel.hadoop.dfs.nameservices: usdp-bing seatunnel.hadoop.dfs.ha.namenodes.usdp-bing: nn1,nn2 seatunnel.hadoop.dfs.namenode.rpc-address.usdp-bing.nn1: usdp-bing-nn1:8020 seatunnel.hadoop.dfs.namenode.rpc-address.usdp-bing.nn2: usdp-bing-nn2:8020 seatunnel.hadoop.dfs.client.failover.proxy.provider.usdp-bing: org.apache.hadoop.hdfs.server.namenode.ha.ConfiguredFailoverProxyProvider
if HDFS has some other configs in hdfs-site.xml or core-site.xml , just set HDFS config by using seatunnel.hadoop. prefix.
seatunnel: engine: checkpoint: interval: 6000 timeout: 7000 storage: type: hdfs max-retained: 3 plugin-config: storage.type: hdfs fs.defaultFS: file:/// # Ensure that the directory has written permission
When storage:type is hdfs, cache is disabled by default. If you want to enable it, set disable.cache: false
seatunnel: engine: checkpoint: interval: 6000 timeout: 7000 storage: type: hdfs max-retained: 3 plugin-config: storage.type: hdfs disable.cache: false fs.defaultFS: hdfs:///
or
seatunnel: engine: checkpoint: interval: 6000 timeout: 7000 storage: type: hdfs max-retained: 3 plugin-config: storage.type: hdfs disable.cache: false fs.defaultFS: file:///