从端口的角度来解释MySQL-Cluster7.2.8的启动与各节点的连接过程

xinxuaw231

　　 Cluster角色重新分配：
　　 192.168.211.10 mgm + data + sql

　　 192.168.211.9 data + sql
　　 192.168.211.11 + sql (not used)

　　 211.10上开始：

　　 # lsof -i:1186 # 启动管理节点之前
　　 # ndb_mgmd --ndb_nodeid=1 -f /var/lib/mysql-cluster/config.ini #启动管理节点
　　 # lsof -i:1186
　　 有以下提示信息：
　　 COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
ndb_mgmd 8097 root 8u IPv4 71559 TCP   *:mysql-cluster (LISTEN)
ndb_mgmd 8097 root 9u   IPv4 71560   TCP localhost.localdomain:53808->loc )
ndb_mgmd 8097 root 10u   IPv4 71563 TCP   localhost.localdomain:mysql-clus)


　　 command：进程名称；FD：文件描述符，应用程序通过文件描述符来识别该文件；type：文件类型；device size：磁盘文件大小；node：索引节点，即文件在磁盘上的标识；name：打开文件的确切名称。
　　 # ps -A | grep ndb
　　 提示信息：8097 ? 00:00:00 ndb_mgmd
　　 # ndbd --ndb_nodeid=2 #启动数据节点
　　 # lsof -i:2202
　　 COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
ndbd 8166 root 9u IPv4 71794 TCP 192.168.211.10:imtc-map (LISTEN)
# ps -A | grep ndbd
　　   提示信息：
　　 8165 ? 00:00:00 ndbd
8166 ? 00:00:01 ndbd
　　 # lsof -i:1186
　　    提示信息：
　　   COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
ndb_mgmd 8097 root 8u IPv4 71559 TCP *:mysql-cluster (LISTEN)
ndb_mgmd 8097 root 9u IPv4 71560 TCP localhost.localdomain:53808->localhost.localdomain:mysql-cluster (ESTABLISHED)
ndb_mgmd 8097 root 10u IPv4 71563 TCP localhost.localdomain:mysql-cluster->localhost.localdomain:53808 (ESTABLISHED)
ndb_mgmd 8097 root 11u IPv4 71787 TCP 192.168.211.10:mysql-cluster->192.168.211.10:37721 (ESTABLISHED)
ndb_mgmd 8097 root 12u IPv4 71791 TCP 192.168.211.10:mysql-cluster->192.168.211.10:37722 (ESTABLISHED)
ndbd 8165 root 3u IPv4 71786 TCP 192.168.211.10:37721->192.168.211.10:mysql-cluster (ESTABLISHED)
ndbd 8166 root 3u IPv4 71786 TCP 192.168.211.10:37721->192.168.211.10:mysql-cluster (ESTABLISHED)
ndbd 8166 root 7u IPv4 71790 TCP 192.168.211.10:37722->192.168.211.10:mysql-cluster (ESTABLISHED)
# ndbd --ndb_nodeid=3 #211.9
　　 # ps -A | grep ndb
　　 7029 ? 00:00:00 ndbd
7030 ? 00:00:04 ndbd

　　 # lsof -i:2202 # 211.9
COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
ndbd 7030 root 9u IPv4 14285 TCP 192.168.211.9:imtc-map (LISTEN)
ndbd 7030 root 12u IPv4 14288 TCP 192.168.211.9:52533->192.168.211.10:imtc-map (ESTABLISHED)
　　 # lsof -i:2202 # 211.10
COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
ndbd 8166 root 9u IPv4 71794 TCP 192.168.211.10:imtc-map (LISTEN)
ndbd 8166 root 22u IPv4 71933 TCP 192.168.211.10:imtc-map->192.168.211.9:52533 (ESTABLISHED)
　　 # lsof -i:1186 # 211.10
COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
ndb_mgmd 8097 root 8u IPv4 71559 TCP *:mysql-cluster (LISTEN)
ndb_mgmd 8097 root 9u IPv4 71560 TCP localhost.localdomain:53808->localhost.localdomain:mysql-cluster (ESTABLISHED)
ndb_mgmd 8097 root 10u IPv4 71563 TCP localhost.localdomain:mysql-cluster->localhost.localdomain:53808 (ESTABLISHED)
ndb_mgmd 8097 root 11u IPv4 71787 TCP 192.168.211.10:mysql-cluster->192.168.211.10:37721 (ESTABLISHED)
ndb_mgmd 8097 root 12u IPv4 71791 TCP 192.168.211.10:mysql-cluster->192.168.211.10:37722 (ESTABLISHED)
ndb_mgmd 8097 root 13u IPv4 71931 TCP 192.168.211.10:mysql-cluster->192.168.211.9:50749 (ESTABLISHED)
ndb_mgmd 8097 root 14u IPv4 71932 TCP 192.168.211.10:mysql-cluster->192.168.211.9:50750 (ESTABLISHED)
ndbd 8165 root 3u IPv4 71786 TCP 192.168.211.10:37721->192.168.211.10:mysql-cluster (ESTABLISHED)
ndbd 8166 root 3u IPv4 71786 TCP 192.168.211.10:37721->192.168.211.10:mysql-cluster (ESTABLISHED)
ndbd 8166 root 7u IPv4 71790 TCP 192.168.211.10:37722->192.168.211.10:mysql-cluster (ESTABLISHED)
　　 # lsof -i:3306 # 211.9
　　 # mysqld_safe --ndb_nodeid=5 --user=mysql & # 211.9

　　 # ps -A | grep mysql
　　 提示信息：
　　 7094 pts/2 00:00:00 mysqld_safe
7252 pts/2 00:00:00 mysqld
　　 # lsof -i:3306 # 211.9
COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
mysqld 7252 mysql 17u IPv4 14530 TCP *:mysql (LISTEN)
　　 # lsof -i:1186 # 211.10
COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
ndb_mgmd 8097 root 8u IPv4 71559 TCP *:mysql-cluster (LISTEN)
ndb_mgmd 8097 root 9u IPv4 71560 TCP localhost.localdomain:53808->localhost.localdomain:mysql-cluster (ESTABLISHED)
ndb_mgmd 8097 root 10u IPv4 71563 TCP localhost.localdomain:mysql-cluster->localhost.localdomain:53808 (ESTABLISHED)
ndb_mgmd 8097 root 11u IPv4 71787 TCP 192.168.211.10:mysql-cluster->192.168.211.10:37721 (ESTABLISHED)
ndb_mgmd 8097 root 12u IPv4 71791 TCP 192.168.211.10:mysql-cluster->192.168.211.10:37722 (ESTABLISHED)
ndb_mgmd 8097 root 13u IPv4 71931 TCP 192.168.211.10:mysql-cluster->192.168.211.9:50749 (ESTABLISHED)
ndb_mgmd 8097 root 14u IPv4 71932 TCP 192.168.211.10:mysql-cluster->192.168.211.9:50750 (ESTABLISHED)
ndb_mgmd 8097 root 15u IPv4 72005 TCP 192.168.211.10:mysql-cluster->192.168.211.9:45770 (ESTABLISHED)
ndbd 8165 root 3u IPv4 71786 TCP 192.168.211.10:37721->192.168.211.10:mysql-cluster (ESTABLISHED)
ndbd 8166 root 3u IPv4 71786 TCP 192.168.211.10:37721->192.168.211.10:mysql-cluster (ESTABLISHED)
ndbd 8166 root 7u IPv4 71790 TCP 192.168.211.10:37722->192.168.211.10:mysql-cluster (ESTABLISHED)
# lsof -i:3306 # 211.10
　　 没有提示信息，端口没有被占用。
　　 # mysqld_safe --ndb_nodeid=4 --user=mysql & # 211.10

　　 # ps -A | grep mysql # 211.10

　　 8290 pts/2 00:00:00 mysqld_safe
8448 pts/2 00:00:00 mysqld
　　 # lsof -i:3306 # 211.10
　　 没有提示信息，端口没有被占用。所以mysqld_safe命令启动时没有利用3306端口，而在my.cnf中是指定3306的。

　　  # lsof -i:1186 # 211.10

　　 COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
ndb_mgmd 8097 root 8u IPv4 71559 TCP *:mysql-cluster (LISTEN)
ndb_mgmd 8097 root 9u IPv4 71560 TCP localhost.localdomain:53808->localhost.localdomain:mysql-cluster (ESTABLISHED)
ndb_mgmd 8097 root 10u IPv4 71563 TCP localhost.localdomain:mysql-cluster->localhost.localdomain:53808 (ESTABLISHED)
ndb_mgmd 8097 root 11u IPv4 71787 TCP 192.168.211.10:mysql-cluster->192.168.211.10:37721 (ESTABLISHED)
ndb_mgmd 8097 root 12u IPv4 71791 TCP 192.168.211.10:mysql-cluster->192.168.211.10:37722 (ESTABLISHED)
ndb_mgmd 8097 root 13u IPv4 71931 TCP 192.168.211.10:mysql-cluster->192.168.211.9:50749 (ESTABLISHED)
ndb_mgmd 8097 root 14u IPv4 71932 TCP 192.168.211.10:mysql-cluster->192.168.211.9:50750 (ESTABLISHED)
ndb_mgmd 8097 root 15u IPv4 72005 TCP 192.168.211.10:mysql-cluster->192.168.211.9:45770 (ESTABLISHED)
ndb_mgmd 8097 root 16u IPv4 72190 TCP 192.168.211.10:mysql-cluster->192.168.211.10:38109 (ESTABLISHED)
ndbd 8165 root 3u IPv4 71786 TCP 192.168.211.10:37721->192.168.211.10:mysql-cluster (ESTABLISHED)
ndbd 8166 root 3u IPv4 71786 TCP 192.168.211.10:37721->192.168.211.10:mysql-cluster (ESTABLISHED)
ndbd 8166 root 7u IPv4 71790 TCP 192.168.211.10:37722->192.168.211.10:mysql-cluster (ESTABLISHED)
mysqld 8448 mysql 10u IPv4 72189 TCP 192.168.211.10:38109->192.168.211.10:mysql-cluster (ESTABLISHED)


　　 # lsof -i:3307 # 修改过211.10上的my.cnf中的[mysqld] port = 3307
COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
mysqld 8448 mysql 17u IPv4 72242 TCP *:opsession-prxy (LISTEN)
　　 # lsof -i:1186 # 211.9
　　 COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
ndbd 7029 root 3u IPv4 14279 TCP 192.168.211.9:50749->192.168.211.10:mysql-cluster (ESTABLISHED)
ndbd 7030 root 3u IPv4 14279 TCP 192.168.211.9:50749->192.168.211.10:mysql-cluster (ESTABLISHED)
ndbd 7030 root 7u IPv4 14282 TCP 192.168.211.9:50750->192.168.211.10:mysql-cluster (ESTABLISHED)
mysqld 7252 mysql 10u IPv4 14520 TCP 192.168.211.9:45770->192.168.211.10:mysql-cluster (ESTABLISHED)


　　 # lsof -i:3306 # 211.9
COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
mysqld 7252 mysql 17u IPv4 14530 TCP *:mysql (LISTEN)
　　

　　 从端口上来看，是连接成功的。但是为什么这样的集群环境中211.10上的SQL节点连接不上？
　　 原因：在集群中，有可能遇到这种情况，有些SQL节点连接不上，比如，在>mgm show命令下面，提示55.10上的SQL节点连接不上，此时，通过检查该节点上的配置文件my.cnf正确，数据库初始化也正确，匿名用户也已经删除，就是找不到原因为什么连接不上，此时，大家可以去55.9上查看该节点的防火墙是否关闭，如果9上的防火墙关闭，那么10上的SQL节点是连接不进去的。而数据节点是可以连接的。