Deploy a DM Cluster Using TiUP
TiUP is a cluster operation and maintenance tool introduced in TiDB 4.0. TiUP provides TiUP DM, a cluster management component written in Golang. By using TiUP DM, you can easily perform daily TiDB Data Migration (DM) operations, including deploying, starting, stopping, destroying, scaling, and upgrading a DM cluster, and manage DM cluster parameters.
TiUP supports deploying DM v2.0 or later DM versions. This document introduces how to deploy DM clusters of different topologies.
Prerequisites
When DM performs a full data replication task, the DM-worker is bound with only one upstream database. The DM-worker first exports the full amount of data locally, and then imports the data into the downstream database. Therefore, the worker's host space must be large enough to store all upstream tables to be exported. The storage path is specified later when you create the task.
In addition, you need to meet the hardware and software requirements when deploying a DM cluster.
Step 1: Install TiUP on the control machine
Log in to the control machine using a regular user account (take the tidb
user as an example). All the following TiUP installation and cluster management operations can be performed by the tidb
user.
Install TiUP by executing the following command:
curl --proto '=https' --tlsv1.2 -sSf https://tiup-mirrors.pingcap.com/install.sh | shAfter the installing,
~/.bashrc
has been modified to add TiUP to PATH, so you need to open a new terminal or redeclare the global environment variablessource ~/.bashrc
to use it.Install the TiUP DM component:
tiup install dm dmctl
Step 2: Edit the initialization configuration file
According to the intended cluster topology, you need to manually create and edit the cluster initialization configuration file.
You need to create a YAML configuration file (named topology.yaml
for example) according to the configuration file template. For other scenarios, edit the configuration accordingly.
You can use the command tiup dm template > topology.yaml
to generate a configuration file template quickly.
The configuration of deploying three DM-masters, three DM-workers, and one monitoring component instance is as follows:
# The global variables apply to all other components in the configuration. If one specific value is missing in the component instance, the corresponding global variable serves as the default value.
global:
user: "tidb"
ssh_port: 22
deploy_dir: "/dm-deploy"
data_dir: "/dm-data"
server_configs:
master:
log-level: info
# rpc-timeout: "30s"
# rpc-rate-limit: 10.0
# rpc-rate-burst: 40
worker:
log-level: info
master_servers:
- host: 10.0.1.11
name: master1
ssh_port: 22
port: 8261
# peer_port: 8291
# deploy_dir: "/dm-deploy/dm-master-8261"
# data_dir: "/dm-data/dm-master-8261"
# log_dir: "/dm-deploy/dm-master-8261/log"
# numa_node: "0,1"
# The following configs are used to overwrite the `server_configs.master` values.
config:
log-level: info
# rpc-timeout: "30s"
# rpc-rate-limit: 10.0
# rpc-rate-burst: 40
- host: 10.0.1.18
name: master2
ssh_port: 22
port: 8261
- host: 10.0.1.19
name: master3
ssh_port: 22
port: 8261
# If you do not need to ensure high availability of the DM cluster, deploy only one DM-master node, and the number of deployed DM-worker nodes must be no less than the number of upstream MySQL/MariaDB instances to be migrated.
# To ensure high availability of the DM cluster, it is recommended to deploy three DM-master nodes, and the number of deployed DM-worker nodes must exceed the number of upstream MySQL/MariaDB instances to be migrated (for example, the number of DM-worker nodes is two more than the number of upstream instances).
worker_servers:
- host: 10.0.1.12
ssh_port: 22
port: 8262
# deploy_dir: "/dm-deploy/dm-worker-8262"
# log_dir: "/dm-deploy/dm-worker-8262/log"
# numa_node: "0,1"
# The following configs are used to overwrite the `server_configs.worker` values.
config:
log-level: info
- host: 10.0.1.19
ssh_port: 22
port: 8262
monitoring_servers:
- host: 10.0.1.13
ssh_port: 22
port: 9090
# deploy_dir: "/tidb-deploy/prometheus-8249"
# data_dir: "/tidb-data/prometheus-8249"
# log_dir: "/tidb-deploy/prometheus-8249/log"
grafana_servers:
- host: 10.0.1.14
port: 3000
# deploy_dir: /tidb-deploy/grafana-3000
alertmanager_servers:
- host: 10.0.1.15
ssh_port: 22
web_port: 9093
# cluster_port: 9094
# deploy_dir: "/tidb-deploy/alertmanager-9093"
# data_dir: "/tidb-data/alertmanager-9093"
# log_dir: "/tidb-deploy/alertmanager-9093/log"
For more master_servers.host.config
parameter description, refer to master parameter. For more worker_servers.host.config
parameter description, refer to worker parameter.
Step 3: Execute the deployment command
tiup dm deploy ${name} ${version} ./topology.yaml -u ${ssh_user} [-p] [-i /home/root/.ssh/gcp_rsa]
The parameters used in this step are as follows.
Parameter | Description |
---|---|
${name} | The name of the DM cluster, eg: dm-test |
${version} | The version of the DM cluster. You can see other supported versions by running tiup list dm-master . |
./topology.yaml | The path of the topology configuration file. |
-u or --user | Log in to the target machine as the root user or other user account with ssh and sudo privileges to complete the cluster deployment. |
-p or --password | The password of target hosts. If specified, password authentication is used. |
-i or --identity_file | The path of the SSH identity file. If specified, public key authentication is used (default "/root/.ssh/id_rsa"). |
At the end of the output log, you will see Deployed cluster `dm-test` successfully
. This indicates that the deployment is successful.
Step 4: Check the clusters managed by TiUP
tiup dm list
TiUP supports managing multiple DM clusters. The command above outputs information of all the clusters currently managed by TiUP, including the name, deployment user, version, and secret key information:
Name User Version Path PrivateKey
---- ---- ------- ---- ----------
dm-test tidb ${version} /root/.tiup/storage/dm/clusters/dm-test /root/.tiup/storage/dm/clusters/dm-test/ssh/id_rsa
Step 5: Check the status of the deployed DM cluster
To check the status of the dm-test
cluster, execute the following command:
tiup dm display dm-test
Expected output includes the instance ID, role, host, listening port, and status (because the cluster is not started yet, so the status is Down
/inactive
), and directory information.
Step 6: Start the TiDB cluster
tiup dm start dm-test
If the output log includes Started cluster `dm-test` successfully
, the start is successful.
Step 7: Verify the running status of the TiDB cluster
Check the DM cluster status using TiUP:
tiup dm display dm-test
If the Status
is Up
in the output, the cluster status is normal.
Step 8: Managing migration tasks using dmctl
dmctl is a command-line tool used to control DM clusters. You are recommended to use dmctl via TiUP.
dmctl supports both the command mode and the interactive mode. For details, see Maintain DM Clusters Using dmctl.