deployment
Deployment SeaTunnel Engine
1. Downloadโ
SeaTunnel Engine is the default engine of SeaTunnel. The installation package of SeaTunnel already contains all the contents of SeaTunnel Engine.
2 Config SEATUNNEL_HOMEโ
You can config SEATUNNEL_HOME by add /etc/profile.d/seatunnel.sh file. The content of /etc/profile.d/seatunnel.sh are
export SEATUNNEL_HOME=${seatunnel install path}
export PATH=$PATH:$SEATUNNEL_HOME/bin
3. Config SeaTunnel Engine JVM optionsโ
SeaTunnel Engine supported two ways to set jvm options.
Add JVM Options to
$SEATUNNEL_HOME/bin/seatunnel-cluster.sh.Modify the
$SEATUNNEL_HOME/bin/seatunnel-cluster.shfile and addJAVA_OPTS="-Xms2G -Xmx2G"in the first line.Add JVM Options when start SeaTunnel Engine. For example
seatunnel-cluster.sh -DJvmOption="-Xms2G -Xmx2G"
4. Config SeaTunnel Engineโ
SeaTunnel Engine provides many functions, which need to be configured in seatunnel.yaml.
4.1 Backup countโ
SeaTunnel Engine implement cluster management based on Hazelcast IMDG. The state data of cluster(Job Running State, Resource State) are storage is Hazelcast IMap. The data saved in Hazelcast IMap will be distributed and stored in all nodes of the cluster. Hazelcast will partition the data stored in Imap. Each partition can specify the number of backups. Therefore, SeaTunnel Engine can achieve cluster HA without using other services(for example zookeeper).
The backup count is to define the number of synchronous backups. For example, if it is set to 1, backup of a partition will be placed on one other member. If it is 2, it will be placed on two other members.
We suggest the value of backup-count is the min(1, max(5, N/2)). N is the number of the cluster node.
seatunnel:
engine:
backup-count: 1
# other config
4.2 Slot serviceโ
The number of Slots determines the number of TaskGroups the cluster node can run in parallel. SeaTunnel Engine is a data synchronization engine and most jobs are IO intensive.
Dynamic Slot is suggest.
seatunnel:
engine:
slot-service:
dynamic-slot: true
# other config
4.3 Checkpoint Managerโ
Like Flink, SeaTunnel Engine support ChandyโLamport algorithm. Therefore, SeaTunnel Engine can realize data synchronization without data loss and duplication.
interval
The interval between two checkpoints, unit is milliseconds. If the checkpoint.interval parameter is configured in the env of the job config file, the value set here will be overwritten.
timeout
The timeout of a checkpoint. If a checkpoint cannot be completed within the timeout period, a checkpoint failure will be triggered. Therefore, Job will be restored.
Example
seatunnel:
engine:
backup-count: 1
print-execution-info-interval: 10
slot-service:
dynamic-slot: true
checkpoint:
interval: 300000
timeout: 10000
checkpoint storage
About the checkpoint storage, you can see checkpoint storage
4.4 Historical Job expiration Configโ
The information about each completed Job, such as status, counters, and error logs, is stored in the IMap object. As the number of running jobs increases, the memory increases and eventually the memory will overflow. Therefore, you can adjust the history-job-expire-minutes parameter to solve this problem. The time unit of this parameter is minute. The default value is 1440 minutes, that is, one day.
Example
seatunnel:
engine:
history-job-expire-minutes: 1440
5. Config SeaTunnel Engine Serverโ
All SeaTunnel Engine Server config in hazelcast.yaml file.
5.1 cluster-nameโ
The SeaTunnel Engine nodes use the cluster name to determine whether the other is a cluster with themselves. If the cluster names between the two nodes are different, the SeaTunnel Engine will reject the service request.
5.2 Networkโ
Base on Hazelcast, A SeaTunnel Engine cluster is a network of cluster members that run SeaTunnel Engine Server. Cluster members automatically join together to form a cluster. This automatic joining takes place with various discovery mechanisms that the cluster members use to find each other.
Please note that, after a cluster is formed, communication between cluster members is always via TCP/IP, regardless of the discovery mechanism used.
SeaTunnel Engine uses the following discovery mechanisms.
TCPโ
You can configure SeaTunnel Engine to be a full TCP/IP cluster. See the Discovering Members by TCP section for configuration details.
An example is like this hazelcast.yaml
hazelcast:
cluster-name: seatunnel
network:
join:
tcp-ip:
enabled: true
member-list:
- hostname1
port:
auto-increment: false
port: 5801
properties:
hazelcast.logging.type: log4j2
TCP is our suggest way in a standalone SeaTunnel Engine cluster.
On the other hand, Hazelcast provides some other service discovery methods. For details, please refer to hazelcast network
5.3 Mapโ
MapStores connect to an external data store only when they are configured on a map. This topic explains how to configure a map with a MapStore. For details, please refer to hazelcast map
type
The type of imap persistence, currently only supports hdfs.
namespace
It is used to distinguish data storage locations of different business, like OSS bucket name.
clusterName
This parameter is primarily used for cluster isolation, we can use this to distinguish different cluster, like cluster1, cluster2 and this is also used to distinguish different business
fs.defaultFS
We used hdfs api read/write file, so used this storage need provide hdfs configuration
if you used HDFS, you can config like this:
map:
engine*:
map-store:
enabled: true
initial-mode: EAGER
factory-class-name: org.apache.seatunnel.engine.server.persistence.FileMapStoreFactory
properties:
type: hdfs
namespace: /tmp/seatunnel/imap
clusterName: seatunnel-cluster
storage.type: hdfs
fs.defaultFS: hdfs://localhost:9000
If there is no HDFS and your cluster only have one node, you can config to use local file like this:
map:
engine*:
map-store:
enabled: true
initial-mode: EAGER
factory-class-name: org.apache.seatunnel.engine.server.persistence.FileMapStoreFactory
properties:
type: hdfs
namespace: /tmp/seatunnel/imap
clusterName: seatunnel-cluster
storage.type: hdfs
fs.defaultFS: file:///
if you used OSS, you can config like this:
map:
engine*:
map-store:
enabled: true
initial-mode: EAGER
factory-class-name: org.apache.seatunnel.engine.server.persistence.FileMapStoreFactory
properties:
type: hdfs
namespace: /tmp/seatunnel/imap
clusterName: seatunnel-cluster
storage.type: oss
block.size: block size(bytes)
oss.bucket: oss://bucket name/
fs.oss.accessKeyId: OSS access key id
fs.oss.accessKeySecret: OSS access key secret
fs.oss.endpoint: OSS endpoint
fs.oss.credentials.provider: org.apache.hadoop.fs.aliyun.oss.AliyunCredentialsProvider
6. Config SeaTunnel Engine Clientโ
All SeaTunnel Engine Client config in hazelcast-client.yaml.
6.1 cluster-nameโ
The Client must have the same cluster-name with the SeaTunnel Engine. Otherwise, SeaTunnel Engine will reject the client request.
6.2 Networkโ
cluster-members
All SeaTunnel Engine Server Node address need add to here.
hazelcast-client:
cluster-name: seatunnel
properties:
hazelcast.logging.type: log4j2
network:
cluster-members:
- hostname1:5801
7. Start SeaTunnel Engine Server Nodeโ
Can be started by a daemon with -d.
mkdir -p $SEATUNNEL_HOME/logs
./bin/seatunnel-cluster.sh -d
The logs will write in $SEATUNNEL_HOME/logs/seatunnel-engine-server.log
8. Install SeaTunnel Engine Clientโ
You only need to copy the $SEATUNNEL_HOME directory on the SeaTunnel Engine node to the Client node and config the SEATUNNEL_HOME like SeaTunnel Engine Server Node.