TiDB Binlog User Guide

This document describes how to deploy the Kafka version of TiDB Binlog.

About TiDB Binlog

TiDB Binlog is a tool for enterprise users to collect binlog files for TiDB and provide real-time backup and replication.

TiDB Binlog supports the following scenarios:

• Data replication: to replicate TiDB cluster data to other databases
• Real-time backup and recovery: to back up TiDB cluster data, and recover in case of cluster outages

TiDB Binlog architecture

The TiDB Binlog architecture is as follows:

The TiDB Binlog cluster mainly consists of three components:

Pump

Pump is a daemon that runs on the background of each TiDB host. Its main function is to record the binlog files generated by TiDB in real time and write to the file in the disk sequentially.

Drainer

Drainer collects binlog files from each Pump node, converts them into specified database-compatible SQL statements in the commit order of the transactions in TiDB, and replicates to the target database or writes to the file sequentially.

Kafka & ZooKeeper

The Kafka cluster stores the binlog data written by Pump and provides the binlog data to Drainer for reading.

Note:

In the local version of TiDB Binlog, the binlog is stored in files, while in the Kafka version, the binlog is stored using Kafka.

Install TiDB Binlog

The corresponding relationship between the tidb-ansible branch and the TiDB version is as follows:

Download Binary for the CentOS 7.3+ platform

# Download the tool package.
wget http://download.pingcap.org/tidb-binlog-kafka-linux-amd64.tar.gz
wget http://download.pingcap.org/tidb-binlog-kafka-linux-amd64.sha256

# Check the file integrity. If the result is OK, the file is correct.
sha256sum -c tidb-binlog-kafka-linux-amd64.sha256

# Extract the package.
tar -xzf tidb-binlog-kafka-linux-amd64.tar.gz
cd tidb-binlog-kafka-linux-amd64

Deploy TiDB Binlog

Note

• You need to deploy a Pump for each TiDB server in the TiDB cluster. Currently, the TiDB server only supports the binlog in UNIX socket.

• When you deploy a Pump manually, to start the service, follow the order of Pump -> TiDB; to stop the service, follow the order of TiDB -> Pump.

  We set the startup parameter binlog-socket as the specified unix socket file path of the corresponding parameter socket in Pump. The final deployment architecture is as follows:

  

• Drainer does not support renaming DDL on the table of the ignored schemas (schemas in the filter list).

• To start Drainer in the existing TiDB cluster, usually you need to do a full backup, get the savepoint, import the full backup, and start Drainer and replicate from the savepoint.

  To guarantee the integrity of data, perform the following operations 10 minutes after Pump is started:

  • Use binlogctl of the tidb-tools project to generate the position for the initial start of Drainer.
  • Do a full backup. For example, back up TiDB using Mydumper.
  • Import the full backup to the target system.

  • The savepoint metadata started by the Kafka version of Drainer is stored in the checkpoint table of the downstream database tidb_binlog by default. If no valid data exists in the checkpoint table, configure initial-commit-ts to make Drainer work from a specified position when it is started:

    bin/drainer --config=conf/drainer.toml --initial-commit-ts=${position}

• The drainer outputs pb and you need to set the following parameters in the configuration file:

  [syncer]
  db-type = "pb"
  disable-dispatch = true
  
  [syncer.to]
  dir = "/path/pb-dir"

• The drainer outputs kafka and you need to set the following parameters in the configuration file:

  [syncer]
  db-type = "kafka"
  
  # when db-type is kafka, you can uncomment this to config the down stream kafka, or it will be the same kafka addrs where drainer pulls binlog from.
  [syncer.to]
  kafka-addrs = "127.0.0.1:9092"
  kafka-version = "0.8.2.0"

  The data which outputs to kafka follows the binlog format sorted by ts and defined by protobuf. See driver to access the data and sync to the down stream.

• Deploy Kafka and ZooKeeper cluster before deploying TiDB Binlog. Make sure that Kafka is 0.9 version or later.

Recommended Kafka cluster configuration

Recommended Kafka parameter configuration

• auto.create.topics.enable = true: if no topic exists, Kafka automatically creates a topic on the broker.
• broker.id: a required parameter to identify the Kafka cluster. Keep the parameter value unique. For example, broker.id = 1.
• fs.file-max = 1000000: Kafka uses a lot of files and network sockets. It is recommended to change the parameter value to 1000000. Change the value using vi /etc/sysctl.conf.
• Configure the following three parameters to 1G, to avoid the failure of writing into Kafka caused by too large a single message when a large number of data is modified in a transaction.
  • message.max.bytes=1073741824
  • replica.fetch.max.bytes=1073741824
  • fetch.message.max.bytes=1073741824

Deploy Pump using TiDB Ansible

• If you have not deployed the Kafka cluster, use the Kafka Ansible to deploy.
• When you deploy the TiDB cluster using TiDB Ansible, edit the tidb-ansible/inventory.ini file, set enable_binlog = True, and configure the zookeeper_addrs variable as the ZooKeeper address of the Kafka cluster. In this way, Pump is deployed while you deploy the TiDB cluster.

Configuration example:

# binlog trigger
enable_binlog = True
# ZooKeeper address of the Kafka cluster. Example:
# zookeeper_addrs = "192.168.0.11:2181,192.168.0.12:2181,192.168.0.13:2181"
# You can also append an optional chroot string to the URLs to specify the root directory for all Kafka znodes. Example:
# zookeeper_addrs = "192.168.0.11:2181,192.168.0.12:2181,192.168.0.13:2181/kafka/123"
zookeeper_addrs = "192.168.0.11:2181,192.168.0.12:2181,192.168.0.13:2181"

Deploy Pump using Binary

A usage example:

Assume that we have three PDs, three ZooKeepers, and one TiDB. The information of each node is as follows:

TiDB="192.168.0.10"
PD1="192.168.0.16"
PD2="192.168.0.15"
PD3="192.168.0.14"
ZK1="192.168.0.13"
ZK2="192.168.0.12"
ZK3="192.168.0.11"

Deploy Drainer/Pump on the machine with the IP address “192.168.0.10”.

The IP address of the corresponding PD cluster is “192.168.0.16,192.168.0.15,192.168.0.14”.

The ZooKeeper IP address of the corresponding Kafka cluster is “192.168.0.13,192.168.0.12,192.168.0.11”.

This example describes how to use Pump/Drainer.

1. Description of Pump command line options

   Usage of Pump:
   -L string
       log level: debug, info, warn, error, fatal (default "info")
   -V
       to print Pump version info
   -addr string
       the RPC address that Pump provides service (-addr= "192.168.0.10:8250")
   -advertise-addr string
       the RPC address that Pump provides external service (-advertise-addr="192.168.0.10:8250")
   -config string
       to configure the file path of Pump; if you specifies the configuration file, Pump reads the configuration first; if the corresponding configuration also exists in the command line argument, Pump uses the command line configuration to cover that in the configuration file
   -data-dir string
       the path of storing Pump data
   -enable-tolerant
       after enabling tolerant, Pump wouldn't return error if it fails to write binlog (default true)
   -zookeeper-addrs string (-zookeeper_addrs="192.168.0.11:2181,192.168.0.12:2181,192.168.0.13:2181")
       the ZooKeeper address; this option gets the Kafka address from ZooKeeper, and you need to keep it the same with the configuration in Kafka
   -gc int
       the maximum days that the binlog is retained (default 7), and 0 means retaining the binlog permanently
   -heartbeat-interval int
       the interval between heartbeats that Pump sends to PD (unit: second)
   -log-file string
       the path of the log file
   -log-rotate string
       the log file rotating frequency (hour/day)
   -metrics-addr string
       the Prometheus Pushgateway address; leaving it empty disables Prometheus push
   -metrics-interval int
       the frequency of reporting monitoring information (default 15, unit: second)
   -pd-urls string
       the node address of the PD cluster (-pd-urls="http://192.168.0.16:2379,http://192.168.0.15:2379,http://192.168.0.14:2379")
   -socket string
       the monitoring address of the unix socket service (default "unix:///tmp/pump.sock")

2. Pump configuration file

   # Pump configuration.
   # the RPC address that Pump provides service (default "192.168.0.10:8250")
   addr = "192.168.0.10:8250"
   
   # the RPC address that Pump provides external service (default "192.168.0.10:8250")
   advertise-addr = ""
   
   # an integer value to control expiry date of the binlog data, indicates how long (in days) the binlog data is stored.
   # (default value is 0, means binlog data would never be removed)
   gc = 7
   
   # the path of storing Pump data
   data-dir = "data.pump"
   
   # the ZooKeeper address; You can set the option to get the Kafka address from ZooKeeper; if the namespace is configured in Kafka, you need to keep the same configuration here
   zookeeper-addrs = "192.168.0.11:2181,192.168.0.12:2181,192.168.0.13:2181"
   # example of the ZooKeeper address that configures the namespace
   zookeeper-addrs = "192.168.0.11:2181,192.168.0.12:2181,192.168.0.13:2181/kafka/123"
   
   # the interval between heartbeats that Pump sends to PD (unit: second)
   heartbeat-interval = 3
   
   # the node address of the PD cluster
   pd-urls = "http://192.168.0.16:2379,http://192.168.0.15:2379,http://192.168.0.14:2379"
   
   # the monitoring address of the unix socket service (default "unix:///tmp/pump.sock")
   socket = "unix:///tmp/pump.sock"

3. Startup example

   ./bin/pump -config pump.toml

Deploy Drainer using Binary

1. Description of Drainer command line arguments

   Usage of Drainer:
   -L string
       log level: debug, info, warn, error, fatal (default "info")
   -V
       to print Pump version info
   -addr string
       the address that Drainer provides service (default "192.168.0.10:8249")
   -c int
       to replicate the downstream concurrency number, and a bigger value means better throughput performance (default 1)
   -config string
       to configure the file path of Drainer; if you specifies the configuration file, Drainer reads the configuration first; if the corresponding configuration also exists in the command line argument, Pump uses the command line configuration to cover that in the configuration file
   -data-dir string
       the path of storing Drainer data (default "data.drainer")
   -zookeeper-addrs string (-zookeeper-addrs="192.168.0.11:2181,192.168.0.12:2181,192.168.0.13:2181")
       the ZooKeeper address; you can set this option to get the Kafka address from ZooKeeper, and you need to keep it the same with the configuration in Kafka
   -dest-db-type string
       the downstream service type of Drainer (default "mysql")
   -detect-interval int
       the interval of detecting Pump's status from PD (default 10, unit: second)
   -disable-dispatch
       whether to disable dispatching sqls in a single binlog; if you set the value to true, it is restored into a single transaction to replicate in the order of each binlog (If the downstream service type is "mysql", set the value to false)
   -ignore-schemas string
       the DB filtering list (default "INFORMATION_SCHEMA,PERFORMANCE_SCHEMA,mysql,test"); does not support the rename DDL operation on the table of ignore schemas
   -initial-commit-ts (default 0)
       If Drainer does not provide related breakpoint information, you can use this option to configure the related breakpoint information
   -log-file string
       the path of the log file
   -log-rotate string
       the log file rotating frequency (hour/day)
   -metrics-addr string
       the Prometheus Pushgateway address; leaving it empty disables Prometheus push
   -metrics-interval int
       the frequency of reporting monitoring information (default 15, unit: second)
   -pd-urls string
       the node address of the PD cluster (-pd-urls="http://192.168.0.16:2379,http://192.168.0.15:2379,http://192.168.0.14:2379")
   -txn-batch int
       the number of SQL statements in a single transaction that is output to the downstream database (default 1)

2. Drainer configuration file

   # Drainer configuration
   
   # the address that Drainer provides service ("192.168.0.10:8249")
   addr = "192.168.0.10:8249"
   
   # the interval of detecting Pump's status from PD (default 10, unit: second)
   detect-interval = 10
   
   # the path of storing Drainer data (default "data.drainer")
   data-dir = "data.drainer"
   
   # the ZooKeeper address; you can use this option to get the Kafka address from ZooKeeper; if the namespace is configured in Kafka, you need to keep the same configuration here
   zookeeper-addrs = "192.168.0.11:2181,192.168.0.12:2181,192.168.0.13:2181"
   # example of the ZooKeeper address that configures the namespace
   zookeeper-addrs = "192.168.0.11:2181,192.168.0.12:2181,192.168.0.13:2181/kafka/123"
   
   # the node address of the PD cluster
   pd-urls = "http://192.168.0.16:2379,http://192.168.0.15:2379,http://192.168.0.14:2379"
   
   # the path of the log file
   log-file = "drainer.log"
   
   # Syncer configuration.
   [syncer]
   
   # the DB filtering list (default "INFORMATION_SCHEMA,PERFORMANCE_SCHEMA,mysql,test")
   # does not support the rename DDL operation on the table of ignore schemas
   ignore-schemas = "INFORMATION_SCHEMA,PERFORMANCE_SCHEMA,mysql"
   
   # the number of SQL statements in a single transaction that is output to the downstream database (default 1)
   txn-batch = 1
   
   # to replicate the downstream concurrency number, and a bigger value means better throughput performance (default 1)
   worker-count = 1
   
   # whether to disable dispatching sqls in a single binlog;
   # if you set the value to true, it is restored into a single transaction to replicate in the order of each binlog (If the downstream service type is "mysql", set the value to false)
   disable-dispatch = false
   
   # the downstream service type of Drainer (default "mysql")
   # valid values: "mysql", "pb"
   db-type = "mysql"
   
   # replicate-do-db priority over replicate-do-table if have same db name
   # and we support regex expression,
   # the regex expression starts with '~'
   
   # replicate-do-db = ["~^b.*","s1"]
   
   # [[syncer.replicate-do-table]]
   # db-name ="test"
   # tbl-name = "log"
   
   # [[syncer.replicate-do-table]]
   # db-name ="test"
   # tbl-name = "~^a.*"
   
   # server parameters of the downstream database when the db-type is set to "mysql"
   [syncer.to]
   host = "192.168.0.10"
   user = "root"
   password = ""
   port = 3306
   
   # the directory of the binlog file when the db-type is set to "pb"
   # [syncer.to]
   # dir = "data.drainer"

3. Startup example

   ./bin/drainer -config drainer.toml

Download PbReader (Linux)

PbReader parses the pb file generated by Drainer and translates it into SQL statements.

CentOS 7+

# Download PbReader package
wget http://download.pingcap.org/pb_reader-latest-linux-amd64.tar.gz
wget http://download.pingcap.org/pb_reader-latest-linux-amd64.sha256

# Check the file integrity. If the result is OK, the file is correct.
sha256sum -c pb_reader-latest-linux-amd64.sha256

# Extract the package.
tar -xzf pb_reader-latest-linux-amd64.tar.gz
cd pb_reader-latest-linux-amd64

The PbReader usage example

./bin/pbReader -binlog-file=${path}/binlog-0000000000000000

Monitor TiDB Binlog

This section introduces how to monitor TiDB Binlog’s status and performance, and display the metrics using Prometheus and Grafana.

Configure Pump/Drainer

Use the Pump service deployed using Ansible. Set metrics in startup parameters.

When you start Drainer, set the two parameters of --metrics-addr and --metrics-interval. Set --metrics-addr as the address of Push Gateway. Set --metrics-interval as the frequency of push (default 15 seconds).

Configure Grafana

Create a Prometheus data source

1. Login the Grafana Web interface.

   • The default address is: http://localhost:3000

   • The default account name: admin

   • The password for the default account: admin

2. Click the Grafana logo to open the sidebar menu.

3. Click “Data Sources” in the sidebar.

4. Click “Add data source”.

5. Specify the data source information:

   • Specify the name for the data source.
   • For Type, select Prometheus.
   • For Url, specify the Prometheus address.
   • Specify other fields as needed.

6. Click “Add” to save the new data source.

Create a Grafana dashboard

1. Click the Grafana logo to open the sidebar menu.

2. On the sidebar menu, click “Dashboards” -> “Import” to open the “Import Dashboard” window.

3. Click “Upload .json File” to upload a JSON file (Download TiDB Grafana Config).

4. Click “Save & Open”. A Prometheus dashboard is created.