搭建MariaDB Galera集群
以下是使用Galera Cluster可以很容易地搭建多个主数据库的构建备忘录。
因此，我將多個實例掛載到LB下，並讓每個實例同時運行AP服務器和DB服務器，並嘗試在每個實例上進行更新和查詢。
因为想尝试在PostgreSQL上构建多主数据库结构，但感觉太难了，所以尝试了看起来简单的MariaDB。
-
- OS: CentOS7, 最小3台で構築
- MariaDB: 10.3.8
这篇文章非常有参考价值。
实际上几乎成了抄袭。
http://www.orangetakam.com/blog/archives/1403
操作系统准备完成。
Vagrantfile的配置
# *- mode: ruby -*-
# vi: set ft=ruby :
Vagrant.configure("2") do |config|
config.vm.define "db1" do |node|
node.vm.provider "virtualbox" do |vm|
vm.name = "db1"
vm.customize ["modifyvm", :id, "--memory", "2048"]
end
node.vm.box = "centos/7"
node.vm.hostname = "db1"
node.vm.network "private_network", ip: "192.168.56.10"
end
config.vm.define "db2" do |node|
node.vm.provider "virtualbox" do |vm|
vm.name = "db2"
vm.customize ["modifyvm", :id, "--memory", "2048"]
end
node.vm.box = "centos/7"
node.vm.hostname = "db2"
node.vm.network "private_network", ip: "192.168.56.20"
end
config.vm.define "db3" do |node|
node.vm.provider "virtualbox" do |vm|
vm.name = "db3"
vm.customize ["modifyvm", :id, "--memory", "2048"]
end
node.vm.box = "centos/7"
node.vm.hostname = "db3"
node.vm.network "private_network", ip: "192.168.56.30"
end
end
操作系统启动
vagrant up db1 db2 db3
禁用SELINUX
您需要按照以下方式编辑/etc/sysconfig/selinux并重新启动。
SELINUX=disabled
SELINUXTYPE=targeted
MariaDB的安装
请执行以下从DB1到DB3的所有工作。
删除已捆绑的MariaDB。
sudo yum info mariadb-libs.x86_64
sudo yum -y remove mariadb-libs.x86_64
配置仓库
curl -sS https://downloads.mariadb.com/MariaDB/mariadb_repo_setup | sudo bash
安装最新版的MariaDB。
sudo yum -y install MariaDB-server MariaDB-client
MariaDB的初始設置
sudo systemctl disable mariadb
sudo systemctl start mariadb
sudo mysql_secure_installation
NOTE: RUNNING ALL PARTS OF THIS SCRIPT IS RECOMMENDED FOR ALL MariaDB
SERVERS IN PRODUCTION USE! PLEASE READ EACH STEP CAREFULLY!
In order to log into MariaDB to secure it, we'll need the current
password for the root user. If you've just installed MariaDB, and
you haven't set the root password yet, the password will be blank,
so you should just press enter here.
Enter current password for root (enter for none):
OK, successfully used password, moving on...
Setting the root password ensures that nobody can log into the MariaDB
root user without the proper authorisation.
Set root password? [Y/n] Y
New password: Pass@0077
Re-enter new password: Pass@0077
Password updated successfully!
Reloading privilege tables..
... Success!
By default, a MariaDB installation has an anonymous user, allowing anyone
to log into MariaDB without having to have a user account created for
them. This is intended only for testing, and to make the installation
go a bit smoother. You should remove them before moving into a
production environment.
Remove anonymous users? [Y/n] Y
... Success!
Normally, root should only be allowed to connect from 'localhost'. This
ensures that someone cannot guess at the root password from the network.
Disallow root login remotely? [Y/n] Y
... Success!
By default, MariaDB comes with a database named 'test' that anyone can
access. This is also intended only for testing, and should be removed
before moving into a production environment.
Remove test database and access to it? [Y/n] Y
- Dropping test database...
... Success!
- Removing privileges on test database...
... Success!
Reloading the privilege tables will ensure that all changes made so far
will take effect immediately.
Reload privilege tables now? [Y/n] Y
... Success!
Cleaning up...
All done! If you've completed all of the above steps, your MariaDB
installation should now be secure.
Thanks for using MariaDB!
停止MariaDB
我要在稍后使用Galera Cluster进行启动，所以请先停止它。
sudo systemctl stop mariadb
Galera Cluster的初始设置位于/etc/my.cnf.d/server.cnf中。
db1的初始设置
sudo vi /etc/my.cnf.d/server.cnf
sudo mkdir -p /var/log/mariadb
sudo chown -R mysql:mysql /var/log/mariadb
[server]
[mysqld]
character-set-server=utf8
log-output=FILE
# Error log
log-error="/var/log/mariadb/mysqld.log"
# Query log
general-log=0
general_log_file="/var/log/mariadb/sql.log"
# Slow Query log
slow-query-log=1
slow_query_log_file="/var/log/mariadb/slow.log"
log_queries_not_using_indexes
log_slow_admin_statements
long_query_time=10
[galera]
wsrep_node_address=192.168.56.10
wsrep_node_name=db1
wsrep_cluster_address='gcomm://192.168.56.10,192.168.56.20,192.168.56.30'
wsrep_cluster_name=DevelopCluster
wsrep_provider=/usr/lib64/galera/libgalera_smm.so
binlog_format=row
default_storage_engine=InnoDB
innodb_autoinc_lock_mode=2
wsrep_on=ON
wsrep_sst_method=rsync
wsrep_slave_threads=2
innodb_locks_unsafe_for_binlog=1
[embedded]
[mariadb]
[mariadb-10.3]
DB2的初始设置
sudo vi /etc/my.cnf.d/server.cnf
sudo mkdir /var/log/mariadb
sudo chown -R mysql:mysql /var/log/mariadb
[server]
[mysqld]
character-set-server=utf8
log-output=FILE
# Error log
log-error="/var/log/mariadb/mysqld.log"
# Query log
general-log=0
general_log_file="/var/log/mariadb/sql.log"
# Slow Query log
slow-query-log=1
slow_query_log_file="/var/log/mariadb/slow.log"
log_queries_not_using_indexes
log_slow_admin_statements
long_query_time=10
[galera]
wsrep_node_address=192.168.56.20
wsrep_node_name=db2
wsrep_cluster_address='gcomm://192.168.56.10,192.168.56.20,192.168.56.30'
wsrep_cluster_name=DevelopCluster
wsrep_provider=/usr/lib64/galera/libgalera_smm.so
binlog_format=row
default_storage_engine=InnoDB
innodb_autoinc_lock_mode=2
wsrep_on=ON
wsrep_sst_method=rsync
wsrep_slave_threads=2
innodb_locks_unsafe_for_binlog=1
[embedded]
[mariadb]
[mariadb-10.3]
db3的初始设置
sudo vi /etc/my.cnf.d/server.cnf
sudo mkdir -p /var/log/mariadb
sudo chown -R mysql:mysql /var/log/mariadb
[server]
[mysqld]
character-set-server=utf8
log-output=FILE
# Error log
log-error="/var/log/mariadb/mysqld.log"
# Query log
general-log=0
general_log_file="/var/log/mariadb/sql.log"
# Slow Query log
slow-query-log=1
slow_query_log_file="/var/log/mariadb/slow.log"
log_queries_not_using_indexes
log_slow_admin_statements
long_query_time=10
[galera]
wsrep_node_address=192.168.56.30
wsrep_node_name=db3
wsrep_cluster_address='gcomm://192.168.56.10,192.168.56.20,192.168.56.30'
wsrep_cluster_name=DevelopCluster
wsrep_provider=/usr/lib64/galera/libgalera_smm.so
binlog_format=row
default_storage_engine=InnoDB
innodb_autoinc_lock_mode=2
wsrep_on=ON
wsrep_sst_method=rsync
wsrep_slave_threads=2
innodb_locks_unsafe_for_binlog=1
[embedded]
[mariadb]
[mariadb-10.3]
启动Galera集群
确认启动MariaDB Galera Cluster中的db1节点
这是对db1的启动确认。
此时，db2和db3处于停止状态。
在Galera Cluster中，如果初始配置文件中的”wsrep_cluster_address”所描述的节点没有启动，就无法启动。当启动第一个节点（即第一节点）时，其他节点都必须处于停止状态。
首先，我们可以使用galera_new_cluster命令来启动第一个节点。
sudo galera_new_cluster
请执行”show status like ‘wsrep_%’;”，以确认以下事项。
[确认事项]
-
- wsrep_cluster_status: Primary
-
- wsrep_incoming_addresses: 設定したアドレス
- wsrep_local_state_comment: Synced
[vagrant@db1 my.cnf.d]$ mysql -u root -p
Enter password:
MariaDB [(none)]> show status like 'wsrep_%';
+------------------------------+--------------------------------------+
| Variable_name | Value |
+------------------------------+--------------------------------------+
| wsrep_apply_oooe | 0.000000 |
| wsrep_apply_oool | 0.000000 |
| wsrep_apply_window | 0.000000 |
| wsrep_causal_reads | 0 |
| wsrep_cert_deps_distance | 0.000000 |
| wsrep_cert_index_size | 0 |
| wsrep_cert_interval | 0.000000 |
| wsrep_cluster_conf_id | 1 |
| wsrep_cluster_size | 1 |
| wsrep_cluster_state_uuid | 5ea4eb1f-8bff-11e8-934d-7aa2eaa06ac1 |
| wsrep_cluster_status | Primary |
| wsrep_commit_oooe | 0.000000 |
| wsrep_commit_oool | 0.000000 |
| wsrep_commit_window | 0.000000 |
| wsrep_connected | ON |
| wsrep_desync_count | 0 |
| wsrep_evs_delayed | |
| wsrep_evs_evict_list | |
| wsrep_evs_repl_latency | 0/0/0/0/0 |
| wsrep_evs_state | OPERATIONAL |
| wsrep_flow_control_paused | 0.000000 |
| wsrep_flow_control_paused_ns | 0 |
| wsrep_flow_control_recv | 0 |
| wsrep_flow_control_sent | 0 |
| wsrep_gcomm_uuid | 5ea35535-8bff-11e8-90ef-6b5cfed70296 |
| wsrep_incoming_addresses | 192.168.56.10:3306 |
| wsrep_last_committed | 0 |
| wsrep_local_bf_aborts | 0 |
| wsrep_local_cached_downto | 18446744073709551615 |
| wsrep_local_cert_failures | 0 |
| wsrep_local_commits | 0 |
| wsrep_local_index | 0 |
| wsrep_local_recv_queue | 0 |
| wsrep_local_recv_queue_avg | 0.500000 |
| wsrep_local_recv_queue_max | 2 |
| wsrep_local_recv_queue_min | 0 |
| wsrep_local_replays | 0 |
| wsrep_local_send_queue | 0 |
| wsrep_local_send_queue_avg | 0.000000 |
| wsrep_local_send_queue_max | 1 |
| wsrep_local_send_queue_min | 0 |
| wsrep_local_state | 4 |
| wsrep_local_state_comment | Synced |
| wsrep_local_state_uuid | 5ea4eb1f-8bff-11e8-934d-7aa2eaa06ac1 |
| wsrep_protocol_version | 8 |
| wsrep_provider_name | Galera |
| wsrep_provider_vendor | Codership Oy <info@codership.com> |
| wsrep_provider_version | 25.3.23(r3789) |
| wsrep_ready | ON |
| wsrep_received | 2 |
| wsrep_received_bytes | 140 |
| wsrep_repl_data_bytes | 0 |
| wsrep_repl_keys | 0 |
| wsrep_repl_keys_bytes | 0 |
| wsrep_repl_other_bytes | 0 |
| wsrep_replicated | 0 |
| wsrep_replicated_bytes | 0 |
| wsrep_thread_count | 3 |
+------------------------------+--------------------------------------+
58 rows in set (0.001 sec)
MariaDB [(none)]> exit
确认db2的MariaDB Galera Cluster是否已启动
请确认DB2的启动情况。
在此时，DB1已经启动，DB3处于停止状态。
sudo systemctl start mariadb
请确认您已经成功加入了集群。
$ mysql -u root -p
Enter password:
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 11
Server version: 10.3.8-MariaDB MariaDB Server
Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
MariaDB [(none)]> show status like 'wsrep_%';
+------------------------------+---------------------------------------+
| Variable_name | Value |
+------------------------------+---------------------------------------+
| wsrep_apply_oooe | 0.000000 |
| wsrep_apply_oool | 0.000000 |
| wsrep_apply_window | 0.000000 |
| wsrep_causal_reads | 0 |
| wsrep_cert_deps_distance | 0.000000 |
| wsrep_cert_index_size | 0 |
| wsrep_cert_interval | 0.000000 |
| wsrep_cluster_conf_id | 2 |
| wsrep_cluster_size | 2 |
| wsrep_cluster_state_uuid | 5ea4eb1f-8bff-11e8-934d-7aa2eaa06ac1 |
| wsrep_cluster_status | Primary |
| wsrep_commit_oooe | 0.000000 |
| wsrep_commit_oool | 0.000000 |
| wsrep_commit_window | 0.000000 |
| wsrep_connected | ON |
| wsrep_desync_count | 0 |
| wsrep_evs_delayed | |
| wsrep_evs_evict_list | |
| wsrep_evs_repl_latency | 0/0/0/0/0 |
| wsrep_evs_state | OPERATIONAL |
| wsrep_flow_control_paused | 0.000000 |
| wsrep_flow_control_paused_ns | 0 |
| wsrep_flow_control_recv | 0 |
| wsrep_flow_control_sent | 0 |
| wsrep_gcomm_uuid | 58f28b22-8c03-11e8-b913-db00a1269d15 |
| wsrep_incoming_addresses | 192.168.56.10:3306,192.168.56.20:3306 |
| wsrep_last_committed | 0 |
| wsrep_local_bf_aborts | 0 |
| wsrep_local_cached_downto | 18446744073709551615 |
| wsrep_local_cert_failures | 0 |
| wsrep_local_commits | 0 |
| wsrep_local_index | 1 |
| wsrep_local_recv_queue | 0 |
| wsrep_local_recv_queue_avg | 0.000000 |
| wsrep_local_recv_queue_max | 1 |
| wsrep_local_recv_queue_min | 0 |
| wsrep_local_replays | 0 |
| wsrep_local_send_queue | 0 |
| wsrep_local_send_queue_avg | 0.000000 |
| wsrep_local_send_queue_max | 1 |
| wsrep_local_send_queue_min | 0 |
| wsrep_local_state | 4 |
| wsrep_local_state_comment | Synced |
| wsrep_local_state_uuid | 5ea4eb1f-8bff-11e8-934d-7aa2eaa06ac1 |
| wsrep_protocol_version | 8 |
| wsrep_provider_name | Galera |
| wsrep_provider_vendor | Codership Oy <info@codership.com> |
| wsrep_provider_version | 25.3.23(r3789) |
| wsrep_ready | ON |
| wsrep_received | 3 |
| wsrep_received_bytes | 216 |
| wsrep_repl_data_bytes | 0 |
| wsrep_repl_keys | 0 |
| wsrep_repl_keys_bytes | 0 |
| wsrep_repl_other_bytes | 0 |
| wsrep_replicated | 0 |
| wsrep_replicated_bytes | 0 |
| wsrep_thread_count | 3 |
+------------------------------+---------------------------------------+
58 rows in set (0.001 sec)
MariaDB [(none)]> exit
确认启动db3上的MariaDB Galera Cluster。
这是用于确认DB3是否已启动的步骤。
sudo systemctl start mariadb
mysql -u root -p
Enter password:
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 11
Server version: 10.3.8-MariaDB MariaDB Server
Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
MariaDB [(none)]> show status like 'wsrep_%';
+------------------------------+----------------------------------------------------------+
| Variable_name | Value |
+------------------------------+----------------------------------------------------------+
| wsrep_apply_oooe | 0.000000 |
| wsrep_apply_oool | 0.000000 |
| wsrep_apply_window | 0.000000 |
| wsrep_causal_reads | 0 |
| wsrep_cert_deps_distance | 0.000000 |
| wsrep_cert_index_size | 0 |
| wsrep_cert_interval | 0.000000 |
| wsrep_cluster_conf_id | 3 |
| wsrep_cluster_size | 3 |
| wsrep_cluster_state_uuid | 5ea4eb1f-8bff-11e8-934d-7aa2eaa06ac1 |
| wsrep_cluster_status | Primary |
| wsrep_commit_oooe | 0.000000 |
| wsrep_commit_oool | 0.000000 |
| wsrep_commit_window | 0.000000 |
| wsrep_connected | ON |
| wsrep_desync_count | 0 |
| wsrep_evs_delayed | |
| wsrep_evs_evict_list | |
| wsrep_evs_repl_latency | 0.000878738/0.00319743/0.00973027/0.003294/5 |
| wsrep_evs_state | OPERATIONAL |
| wsrep_flow_control_paused | 0.000000 |
| wsrep_flow_control_paused_ns | 0 |
| wsrep_flow_control_recv | 0 |
| wsrep_flow_control_sent | 0 |
| wsrep_gcomm_uuid | f93e0362-8c03-11e8-b220-a3600473017a |
| wsrep_incoming_addresses | 192.168.56.10:3306,192.168.56.20:3306,192.168.56.30:3306 |
| wsrep_last_committed | 0 |
| wsrep_local_bf_aborts | 0 |
| wsrep_local_cached_downto | 18446744073709551615 |
| wsrep_local_cert_failures | 0 |
| wsrep_local_commits | 0 |
| wsrep_local_index | 2 |
| wsrep_local_recv_queue | 0 |
| wsrep_local_recv_queue_avg | 0.000000 |
| wsrep_local_recv_queue_max | 1 |
| wsrep_local_recv_queue_min | 0 |
| wsrep_local_replays | 0 |
| wsrep_local_send_queue | 0 |
| wsrep_local_send_queue_avg | 0.000000 |
| wsrep_local_send_queue_max | 1 |
| wsrep_local_send_queue_min | 0 |
| wsrep_local_state | 4 |
| wsrep_local_state_comment | Synced |
| wsrep_local_state_uuid | 5ea4eb1f-8bff-11e8-934d-7aa2eaa06ac1 |
| wsrep_protocol_version | 8 |
| wsrep_provider_name | Galera |
| wsrep_provider_vendor | Codership Oy <info@codership.com> |
| wsrep_provider_version | 25.3.23(r3789) |
| wsrep_ready | ON |
| wsrep_received | 3 |
| wsrep_received_bytes | 284 |
| wsrep_repl_data_bytes | 0 |
| wsrep_repl_keys | 0 |
| wsrep_repl_keys_bytes | 0 |
| wsrep_repl_other_bytes | 0 |
| wsrep_replicated | 0 |
| wsrep_replicated_bytes | 0 |
| wsrep_thread_count | 3 |
+------------------------------+----------------------------------------------------------+
58 rows in set (0.001 sec)
MariaDB [(none)]> exit
确认数据同步
- db1でデータベース作成
[vagrant@db1 ~]$ mysql -u root -p
Enter password:
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 11
Server version: 10.3.8-MariaDB MariaDB Server
Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
MariaDB [(none)]> create database dev_nagakuray;
Query OK, 1 row affected (0.002 sec)
MariaDB [(none)]> show databases;
+--------------------+
| Database |
+--------------------+
| dev_nagakuray |
| information_schema |
| mysql |
| performance_schema |
+--------------------+
4 rows in set (0.001 sec)
MariaDB [(none)]> use dev_nagakuray
Database changed
MariaDB [dev_nagakuray]> create table test (id int, name varchar(100));
Query OK, 0 rows affected (0.008 sec)
MariaDB [dev_nagakuray]> insert into test (id, name) values (1, 'hogehoge');
Query OK, 1 row affected (0.003 sec)
MariaDB [dev_nagakuray]>
- db2で確認
[vagrant@db2 ~]$ mysql -u root -p
Enter password:
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 11
Server version: 10.3.8-MariaDB MariaDB Server
Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
MariaDB [(none)]> show databases;
+--------------------+
| Database |
+--------------------+
| dev_nagakuray |
| information_schema |
| mysql |
| performance_schema |
+--------------------+
4 rows in set (0.001 sec)
MariaDB [(none)]> use dev_nagakuray
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
MariaDB [dev_nagakuray]> select * from test;
+------+----------+
| id | name |
+------+----------+
| 1 | hogehoge |
+------+----------+
1 row in set (0.000 sec)
MariaDB [dev_nagakuray]> insert into test (id, name) values (2, 'fugafuga');
Query OK, 1 row affected (0.005 sec)
- db3で確認
[vagrant@db3 ~]$ mysql -u root -p
Enter password:
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 12
Server version: 10.3.8-MariaDB MariaDB Server
Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
MariaDB [(none)]> show databases;
+--------------------+
| Database |
+--------------------+
| dev_nagakuray |
| information_schema |
| mysql |
| performance_schema |
+--------------------+
4 rows in set (0.000 sec)
MariaDB [(none)]> use dev_nagakuray
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
MariaDB [dev_nagakuray]> select * from test;
+------+----------+
| id | name |
+------+----------+
| 1 | hogehoge |
| 2 | fugafuga |
+------+----------+
2 rows in set (0.000 sec)
MariaDB [dev_nagakuray]> insert into test (id, name) values (3, 'hanako');
Query OK, 1 row affected (0.003 sec)
注意事项：关于MariaDB Galera Cluster的停止→启动顺序。
- 起動状態時のdb1
sudo cat /var/lib/mysql/grastate.dat
# GALERA saved state
version: 2.1
uuid: 5ea4eb1f-8bff-11e8-934d-7aa2eaa06ac1
seqno: -1
safe_to_bootstrap: 0
- 起動状態時のdb2
sudo cat /var/lib/mysql/grastate.dat
# GALERA saved state
version: 2.1
uuid: 5ea4eb1f-8bff-11e8-934d-7aa2eaa06ac1
seqno: -1
safe_to_bootstrap: 0
- 起動状態時のdb3
sudo cat /var/lib/mysql/grastate.dat
# GALERA saved state
version: 2.1
uuid: 5ea4eb1f-8bff-11e8-934d-7aa2eaa06ac1
seqno: -1
safe_to_bootstrap: 0
如上所述，该文件中的“safe_to_bootstrap”值为“0”。
然后，按照1号机→2号机→3号机的顺序停止。
[vagrant@db1 ~]$ sudo systemctl stop mariadb
[vagrant@db2 ~]$ sudo systemctl stop mariadb
[vagrant@db3 ~]$ sudo systemctl stop mariadb
我们将检查此时的/var/lib/mysql/grastate.dat文件。
- 停止状態時のdb1
[vagrant@db1 ~]$ sudo cat /var/lib/mysql/grastate.dat
# GALERA saved state
version: 2.1
uuid: 5ea4eb1f-8bff-11e8-934d-7aa2eaa06ac1
seqno: 0
safe_to_bootstrap: 0
- 停止状態時のdb2
[vagrant@db2 ~]$ sudo cat /var/lib/mysql/grastate.dat
# GALERA saved state
version: 2.1
uuid: 5ea4eb1f-8bff-11e8-934d-7aa2eaa06ac1
seqno: 0
safe_to_bootstrap: 0
- 停止状態時のdb3
[vagrant@db3 ~]$ sudo cat /var/lib/mysql/grastate.dat
# GALERA saved state
version: 2.1
uuid: 5ea4eb1f-8bff-11e8-934d-7aa2eaa06ac1
seqno: 0
safe_to_bootstrap: 1
在这个时候，从第一台机器启动后会出现以下错误。
[vagrant@db1 ~]$ sudo galera_new_cluster
Job for mariadb.service failed because the control process exited with error code. See "systemctl status mariadb.service" and "journalctl -xe" for details.
必须从设置为1的3号机安全启动。
[vagrant@db3 ~]$ sudo galera_new_cluster
[vagrant@db1 ~]$ sudo systemctl start mariadb
[vagrant@db2 ~]$ sudo systemctl start mariadb
