Percona XtraDB Cluster docker.md

• 拉取Percona XtraDB Cluster鏡像

docker pull percona/percona-xtradb-cluster:5.7

• 官方鏡像下有使用說明

1. One of MYSQLROOTPASSWORD, MYSQLALLOWEMPTYPASSWORD or MYSQLRANDOMROOTPASSWORDmust be defined.三個設置密碼的環境變數必須定義其中一個。
2. The image will create the user xtrabackup@localhost for the XtraBackup SST method. If you want to use a password for the xtrabackup user, set XTRABACKUPPASSWORD.自動定義用戶xtrabackup，可選設置xtrabackup user的密碼，集群啟動後可以查看資料庫mysql表user，確實有該用戶。

1. If you want to use the discovery service (right now only etcd is supported), set the address to DISCOVERYSERVICE. The image will automatically find a running cluser by CLUSTERNAME and join to the existing cluster (or start a new one).可以使用etcd註冊服務，自動生成集群
2. If you want to start without the discovery service, use the CLUSTERJOIN variable. Empty variables will start a new cluster, To join an existing cluster, set CLUSTERJOIN to the list of IP addresses running cluster nodes.不使用etcd，可以手動添加環境變數CLUSTERJOIN 添加集群。
3. 最重要的提示For an example, see thestart_node.sh script.啟動容器的腳本在github上

• start_node.sh源碼

CLUSTER_NAME=${CLUSTER_NAME:-Theistareykjarbunga}ETCD_HOST=${ETCD_HOST:-10.20.2.4:2379}NETWORK_NAME=${CLUSTER_NAME}_netdocker network create -d overlay $NETWORK_NAME echo "Starting new node..."docker run -d -p 3306 --net=$NETWORK_NAME -e MYSQL_ROOT_PASSWORD=Theistareyk -e DISCOVERY_SERVICE=$ETCD_HOST -e CLUSTER_NAME=${CLUSTER_NAME} -e XTRABACKUP_PASSWORD=Theistare percona/percona-xtradb-cluster#--general-log=1 --general_log_file=/var/lib/mysql/general.logecho "Started $(docker ps -l -q)"# --wsrep_cluster_address="gcomm://$QCOMM"

• 修改啟動腳本
  > 啟動腳本可以根據實際使用進行修改，比如我使用的網路是calico，因此直接指定net和ip，使用etcd服務發現，並且不定義XTRABACKUP_PASSWORD

CLUSTER_NAME=pxc_clusterETCD_HOST=xxxx:yyyy echo "Starting new node..."docker run -d -p 3306 --net=xxxx -ip xxxx -e MYSQL_ROOT_PASSWORD=123456 -e CLUSTER_NAME=${CLUSTER_NAME} -e DISCOVERY_SERVICE=${ETCD_HOST} percona/percona-xtradb-cluster:5.7echo "Started $(docker ps -l -q)"

• 分別3台宿主機上執行啟動腳本後，查詢容器狀態

[root@172 ~]# docker psCONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES99735a328750 percona/**percona**-xtradb-cluster:5.7 "/entrypoint.sh " 6 hours ago Up 6 hours pensive_kare

• 查詢etcd服務信息，瀏覽器直接查看

http://${ETCD_HOST}/v2/keys/pxc-cluster/pxc_cluster1/?recursive=true

• 登錄集群中任意一個node，執行DDL或者DML，會發現其他節點進行了同步。pxc要求表必須有主鍵。前面說過會自動註冊一個用戶xtrabackup，查看用戶表確實存在

mysql> select host,user from user ; +-----------+---------------+| host | user |+-----------+---------------+| % | monitor || % | proxy || % | root || localhost | monitor || localhost | mysql.session || localhost | mysql.sys || localhost | root || localhost | xtrabackup |+-----------+---------------+8 rows in set (0.00 sec)

推薦閱讀：