MySQL高可用之PXC安裝部署（續）

来源:https://www.cnblogs.com/aaron8219/archive/2018/08/07/9440255.html
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Preface Yesterday I implemented a three-nodes PXC,but there were some errors when proceeding it.So I decide to research what's wrong with it.The opera ...


  Preface       Yesterday I implemented a three-nodes PXC,but there were some errors when proceeding it.So I decide to research what's wrong with it.The operations and evidences shows below.   Procedure   Fisrt of all,I find out that yesterday's error is due to lack of "socat" package on first node zlm2. 
 1 //Here's the error log of it.
 2 2018-08-08T08:48:18.198487+01:00 0 [Note] WSREP: Initiating SST/IST transfer on DONOR side (wsrep_sst_xtrabackup-v2 --role 'donor' --address '192.168.1.102:4444/xtrabackup_sst//1' --socket '/tmp/mysql3308.sock' --datadir '/data/mysql/mysql3308/data/' --defaults-file '/data/mysql/mysql3308/my3308.cnf' --defaults-group-suffix ''  --binlog '/data/mysql/mysql3308/logs/mysql-bin' --gtid 'bd5525ab-9a15-11e8-aa0f-4b830c783fc7:21')
 3 2018-08-08T08:48:18.200272+01:00 2 [Note] WSREP: DONOR thread signaled with 0
 4 which: no socat in (/usr/sbin:/sbin:/opt/mysql/Percona-XtraDB-Cluster-5.7.22-rel22-29.26.1.Linux.x86_64.ssl102/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin:/usr/local/mysql/bin:/usr/local/zabbix/bin:/usr/local/zabbix/sbin)
 5     2018-08-08T06:48:18.782344Z WSREP_SST: [ERROR] ******************* FATAL ERROR ********************** 
 6     2018-08-08T06:48:18.784043Z WSREP_SST: [ERROR] socat not found in path: /usr/sbin:/sbin:/opt/mysql/Percona-XtraDB-Cluster-5.7.22-rel22-29.26.1.Linux.x86_64.ssl102/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/root/bin:/usr/local/mysql/bin:/usr/local/zabbix/bin:/usr/local/zabbix/sbin
 7     2018-08-08T06:48:18.785926Z WSREP_SST: [ERROR] ****************************************************** 
 8 2018-08-08T08:48:18.786496+01:00 0 [ERROR] WSREP: Process completed with error: wsrep_sst_xtrabackup-v2 --role 'donor' --address '192.168.1.102:4444/xtrabackup_sst//1' --socket '/tmp/mysql3308.sock' --datadir '/data/mysql/mysql3308/data/' --defaults-file '/data/mysql/mysql3308/my3308.cnf' --defaults-group-suffix ''  --binlog '/data/mysql/mysql3308/logs/mysql-bin' --gtid 'bd5525ab-9a15-11e8-aa0f-4b830c783fc7:21': 2 (No such file or directory)
 9 2018-08-08T08:48:18.786587+01:00 0 [ERROR] WSREP: Command did not run: wsrep_sst_xtrabackup-v2 --role 'donor' --address '192.168.1.102:4444/xtrabackup_sst//1' --socket '/tmp/mysql3308.sock' --datadir '/data/mysql/mysql3308/data/' --defaults-file '/data/mysql/mysql3308/my3308.cnf' --defaults-group-suffix ''  --binlog '/data/mysql/mysql3308/logs/mysql-bin' --gtid 'bd5525ab-9a15-11e8-aa0f-4b830c783fc7:21'
10 2018-08-08T08:48:18.787610+01:00 0 [Warning] WSREP: 1.0 (zlm2): State transfer to 0.0 (zlm3) failed: -2 (No such file or directory)
11 
12 [root@zlm2 08:53:31 /data/mysql/mysql3308/data]
13 #rpm -qa|grep socat
14 
15 [root@zlm2 09:11:08 /data/mysql/mysql3308/data]
16 #yum install socat
17 ... //Omitted.
18 
19 Installed:
20   socat.x86_64 0:1.7.3.2-2.el7                                                                                                                       
21 
22 Complete!

 

Restart the PXC mysqld on zlm2.

 1 [root@zlm2 09:21:38 /data/mysql/mysql3308/data]
 2 #mysqladmin -P3308 shutdown
 3 
 4 [root@zlm2 09:22:10 /data/mysql/mysql3308/data]
 5 #ps aux|grep mysqld
 6 mysql     6295  0.1 22.4 1565212 227920 pts/0  Sl   08:47   0:02 mysqld --defaults-file=/data/mysql/mysql3308/my3308.cnf --wsrep-new-cluster
 7 root      6835  0.0  0.0 112640   956 pts/3    R+   09:22   0:00 grep --color=auto mysqld
 8 
 9 [root@zlm2 09:22:15 /data/mysql/mysql3308/data]
10 #ps aux|grep mysqld
11 root      6841  0.0  0.0 112640   960 pts/3    R+   09:22   0:00 grep --color=auto mysqld
12 
13 [root@zlm2 09:30:04 /data/mysql/mysql3308/data]
14 #mysqld --defaults-file=/data/mysql/mysql3308/my3308.cnf --wsrep-new-cluster &
15 [1] 7055
16 
17 [root@zlm2 09:30:20 /data/mysql/mysql3308/data]
18 #ps aux|grep mysqld
19 mysql     7055  0.4 22.1 1564952 224900 pts/3  Sl   09:30   0:02 mysqld --defaults-file=/data/mysql/mysql3308/my3308.cnf --wsrep-new-cluster
20 root      7583  0.0  0.0 112640   956 pts/3    R+   09:39   0:00 grep --color=auto mysqld

 

It still show the ERROR output when node zlm3 startup.

 1 2018-08-08T09:32:14.789691+01:00 0 [Note] WSREP: (e783b5a9, 'tcp://0.0.0.0:4567') connection established to 2bcb8dba tcp://192.168.1.102:4567
 2 2018-08-08T09:32:14.790669+01:00 0 [Note] WSREP: (e783b5a9, 'tcp://0.0.0.0:4567') turning message relay requesting on, nonlive peers: 
 3 2018-08-08T09:32:15.289238+01:00 0 [Note] WSREP: declaring 2bcb8dba at tcp://192.168.1.102:4567 stable
 4 2018-08-08T09:32:15.290161+01:00 0 [Note] WSREP: Node e783b5a9 state primary
 5 2018-08-08T09:32:15.291214+01:00 0 [Note] WSREP: Current view of cluster as seen by this node
 6 view (view_id(PRIM,2bcb8dba,2)
 7 memb {
 8     2bcb8dba,0
 9     e783b5a9,0
10     }
11 joined {
12     }
13 left {
14     }
15 partitioned {
16     }
17 )
18 2018-08-08T09:32:15.291254+01:00 0 [Note] WSREP: Save the discovered primary-component to disk
19 2018-08-08T09:32:15.291707+01:00 0 [Note] WSREP: New COMPONENT: primary = yes, bootstrap = no, my_idx = 1, memb_num = 2
20 2018-08-08T09:32:15.291726+01:00 0 [Note] WSREP: STATE EXCHANGE: Waiting for state UUID.
21 2018-08-08T09:32:15.791844+01:00 0 [Note] WSREP: STATE EXCHANGE: sent state msg: 2c64cc25-9add-11e8-bdeb-67bbb141911b
22 2018-08-08T09:32:15.793169+01:00 0 [Note] WSREP: STATE EXCHANGE: got state msg: 2c64cc25-9add-11e8-bdeb-67bbb141911b from 0 (zlm3)
23 2018-08-08T09:32:15.793198+01:00 0 [Note] WSREP: STATE EXCHANGE: got state msg: 2c64cc25-9add-11e8-bdeb-67bbb141911b from 1 (zlm2)
24 2018-08-08T09:32:15.793205+01:00 0 [Note] WSREP: Quorum results:
25     version    = 4,
26     component  = PRIMARY,
27     conf_id    = 1,
28     members    = 1/2 (primary/total),
29     act_id     = 21,
30     last_appl. = 0,
31     protocols  = 0/8/3 (gcs/repl/appl),
32     group UUID = bd5525ab-9a15-11e8-aa0f-4b830c783fc7
33 2018-08-08T09:32:15.793211+01:00 0 [Note] WSREP: Flow-control interval: [141, 141]
34 2018-08-08T09:32:15.793213+01:00 0 [Note] WSREP: Trying to continue unpaused monitor
35 2018-08-08T09:32:15.793314+01:00 2 [Note] WSREP: REPL Protocols: 8 (3, 2)
36 2018-08-08T09:32:15.793324+01:00 2 [Note] WSREP: New cluster view: global state: bd5525ab-9a15-11e8-aa0f-4b830c783fc7:21, view# 2: Primary, number of nodes: 2, my index: 1, protocol version 3
37 2018-08-08T09:32:15.793327+01:00 2 [Note] WSREP: Setting wsrep_ready to true
38 2018-08-08T09:32:15.793330+01:00 2 [Note] WSREP: Auto Increment Offset/Increment re-align with cluster membership change (Offset: 1 -> 2) (Increment: 1 -> 2)
39 2018-08-08T09:32:15.793332+01:00 2 [Note] WSREP: wsrep_notify_cmd is not defined, skipping notification.
40 2018-08-08T09:32:15.793337+01:00 2 [Note] WSREP: Assign initial position for certification: 21, protocol version: 3
41 2018-08-08T09:32:15.793351+01:00 0 [Note] WSREP: Service thread queue flushed.
42 2018-08-08T09:32:16.392574+01:00 0 [Note] WSREP: Member 0.0 (zlm3) requested state transfer from '*any*'. Selected 1.0 (zlm2)(SYNCED) as donor.
43 2018-08-08T09:32:16.392599+01:00 0 [Note] WSREP: Shifting SYNCED -> DONOR/DESYNCED (TO: 21)
44 2018-08-08T09:32:16.392659+01:00 2 [Note] WSREP: wsrep_notify_cmd is not defined, skipping notification.
45 2018-08-08T09:32:16.392879+01:00 0 [Note] WSREP: Initiating SST/IST transfer on DONOR side (wsrep_sst_xtrabackup-v2 --role 'donor' --address '192.168.1.102:4444/xtrabackup_sst//1' --socket '/tmp/mysql3308.sock' --datadir '/data/mysql/mysql3308/data/' --defaults-file '/data/mysql/mysql3308/my3308.cnf' --defaults-group-suffix ''  --binlog '/data/mysql/mysql3308/logs/mysql-bin' --gtid 'bd5525ab-9a15-11e8-aa0f-4b830c783fc7:21')
46 2018-08-08T09:32:16.396838+01:00 2 [Note] WSREP: DONOR thread signaled with 0
47 2018-08-08T09:32:17.917352+01:00 0 [Note] WSREP: (e783b5a9, 'tcp://0.0.0.0:4567') turning message relay requesting off
48     2018-08-08T07:32:27.003790Z WSREP_SST: [INFO] Streaming the backup to joiner at 192.168.1.102 4444
49 2018-08-08T09:32:27.124206+01:00 4 [Note] Access denied for user 'sst'@'192.168.1.101' (using password: YES)
50 2018-08-08T09:32:27.138281+01:00 5 [Note] Aborted connection 5 to db: 'unconnected' user: 'sst' host: 'localhost' (Got an error reading communication packets)
51     2018-08-08T07:32:27.139336Z WSREP_SST: [ERROR] ******************* FATAL ERROR ********************** 
52     2018-08-08T07:32:27.140923Z WSREP_SST: [ERROR] xtrabackup finished with error: 1.  Check /data/mysql/mysql3308/data//innobackup.backup.log
53 --------------- innobackup.backup.log (START) --------------------
54 xtrabackup: recognized server arguments: --datadir=/data/mysql/mysql3308/data --server-id=1013308 --open_files_limit=65536 --log_bin=/data/mysql/mysql3308/logs/mysql-bin --innodb_data_file_path=ibdata1:100M:autoextend --innodb_buffer_pool_filename=ib_buffer_pool --innodb_log_group_home_dir=./ --innodb_log_files_in_group=3 --innodb_log_file_size=100M --innodb_file_per_table=1 --innodb_open_files=65535 --innodb_page_size=16k --innodb_read_io_threads=4 --innodb_write_io_threads=4 --innodb_io_capacity=200 --innodb_doublewrite=1 --innodb_log_buffer_size=128M --innodb_flush_log_at_trx_commit=1 --innodb_buffer_pool_size=100M --innodb_flush_method=O_DIRECT --defaults_group=mysqld --parallel=4 
55 xtrabackup: recognized client arguments: --datadir=/data/mysql/mysql3308/data --server-id=1013308 --open_files_limit=65536 --log_bin=/data/mysql/mysql3308/logs/mysql-bin --innodb_data_file_path=ibdata1:100M:autoextend --innodb_buffer_pool_filename=ib_buffer_pool --innodb_log_group_home_dir=./ --innodb_log_files_in_group=3 --innodb_log_file_size=100M --innodb_file_per_table=1 --innodb_open_files=65535 --innodb_page_size=16k --innodb_read_io_threads=4 --innodb_write_io_threads=4 --innodb_io_capacity=200 --innodb_doublewrite=1 --innodb_log_buffer_size=128M --innodb_flush_log_at_trx_commit=1 --innodb_buffer_pool_size=100M --innodb_flush_method=O_DIRECT --defaults_group=mysqld --parallel=4 --port=3308 --user=sst --password=* --socket=/tmp/mysql3308.sock --lock-ddl=1 --backup=1 --galera-info=1 --binlog-info=ON --stream=xbstream --target-dir=/tmp/pxc_sst_sn2p/donor_xb_qh5x 
56 180808 09:32:27  version_check Connecting to MySQL server with DSN 'dbi:mysql:;mysql_read_default_group=xtrabackup;port=3308;mysql_socket=/tmp/mysql3308.sock' as 'sst'  (using password: YES).
57 Failed to connect to MySQL server: DBI connect(';mysql_read_default_group=xtrabackup;port=3308;mysql_socket=/tmp/mysql3308.sock','sst',...) failed: Access denied for user 'sst'@'192.168.1.101' (using password: YES) at - line 1314.
58 180808 09:32:27 Connecting to MySQL server host: localhost, user: sst, password: set, port: 3308, socket: /tmp/mysql3308.sock
59 Using server version 5.7.22-22-29.26-log
60 180808 09:32:27 Executing LOCK TABLES FOR BACKUP...
61 Error: failed to execute query SHOW ENGINE INNODB STATUS: Access denied; you need (at least one of) the PROCESS privilege(s) for this operation
62 --------------- innobackup.backup.log (END) ----------------------
63     2018-08-08T07:32:27.143691Z WSREP_SST: [ERROR] ****************************************************** 
64     2018-08-08T07:32:27.145779Z WSREP_SST: [ERROR] Cleanup after exit with status:22
65 2018-08-08T09:32:27.158932+01:00 0 [ERROR] WSREP: Process completed with error: wsrep_sst_xtrabackup-v2 --role 'donor' --address '192.168.1.102:4444/xtrabackup_sst//1' --socket '/tmp/mysql3308.sock' --datadir '/data/mysql/mysql3308/data/' --defaults-file '/data/mysql/mysql3308/my3308.cnf' --defaults-group-suffix ''  --binlog '/data/mysql/mysql3308/logs/mysql-bin' --gtid 'bd5525ab-9a15-11e8-aa0f-4b830c783fc7:21': 22 (Invalid argument)
66 2018-08-08T09:32:27.159041+01:00 0 [ERROR] WSREP: Command did not run: wsrep_sst_xtrabackup-v2 --role 'donor' --address '192.168.1.102:4444/xtrabackup_sst//1' --socket '/tmp/mysql3308.sock' --datadir '/data/mysql/mysql3308/data/' --defaults-file '/data/mysql/mysql3308/my3308.cnf' --defaults-group-suffix ''  --binlog '/data/mysql/mysql3308/logs/mysql-bin' --gtid 'bd5525ab-9a15-11e8-aa0f-4b830c783fc7:21'
67 2018-08-08T09:32:27.160430+01:00 0 [Warning] WSREP: 1.0 (zlm2): State transfer to 0.0 (zlm3) failed: -22 (Invalid argument)
68 
69 //Error: failed to execute query SHOW ENGINE INNODB STATUS: Access denied; you need (at least one of) the PROCESS privilege(s) for this operation.
70 //It seams the user sst@localhost is lack of privilege of "PROCESS".

 

Modify the privilege of user sst@localhost.

 1 (zlm@192.168.1.101 3308)[(none)]>select user,host from mysql.user;
 2 +---------------+-------------+
 3 | user          | host        |
 4 +---------------+-------------+
 5 | zlm           | 192.168.1.% |
 6 | mysql.session | localhost   |
 7 | mysql.sys     | localhost   |
 8 | root          | localhost   |
 9 | sst           | localhost   |
10 +---------------+-------------+
11 5 rows in set (0.02 sec)
12 
13 (zlm@192.168.1.101 3308)[(none)]>show grants for sst@localhost;
14 +---------------------------------------------------------------------------+
15 | Grants for sst@localhost                                                  |
16 +---------------------------------------------------------------------------+
17 | GRANT RELOAD, LOCK TABLES, REPLICATION CLIENT ON *.* TO 'sst'@'localhost' |
18 +---------------------------------------------------------------------------+
19 1 row in set (0.00 sec)
20 
21 (zlm@192.168.1.101 3308)[(none)]>grant process on *.* to 'sst'@'localhost';
22 ERROR 1045 (28000): Access denied for user 'zlm'@'192.168.1.%' (using password: YES)
23 (zlm@192.168.1.101 3308)[(none)]>exit
24 Bye
25 
26 [root@zlm2 10:07:32 ~]
27 #mysql -uroot -pPassw0rd -hlocalhost -S /tmp/mysql3308.sock
28 mysql: [Warning] Using a password on the command line interface can be insecure.
29 Welcome to the MySQL monitor.  Commands end with ; or \g.
30 Your MySQL connection id is 9
31 Server version: 5.7.22-22-29.26-log Percona XtraDB Cluster binary (GPL) 5.7.22-29.26, Revision da86071, wsrep_29.26
32 
33 Copyright (c) 2009-2018 Percona LLC and/or its affiliates
34 Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
35 
36 Oracle is a registered trademark of Oracle Corporation and/or its
37 affiliates. Other names may be trademarks of their respective
38 owners.
39 
40 Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
41 
42 (root@localhost mysql3308.sock)[(none)]>grant process on *.* to sst@localhost;
43 Query OK, 0 rows affected, 1 warning (0.01 sec)
44 
45 (root@localhost mysql3308.sock)[(none)]>show grants for sst@localhost;
46 +------------------------------------------------------------------------------------+
47 | Grants for sst@localhost                                                           |
48 +------------------------------------------------------------------------------------+
49 | GRANT RELOAD, PROCESS, LOCK TABLES, REPLICATION CLIENT ON *.* TO 'sst'@'localhost' |
50 +------------------------------------------------------------------------------------+
51 1 row in set (0.00 sec)

 

Restart PXC again on zlm2.

[root@zlm2 10:11:10 ~]
#ps aux|grep mysqld
mysql     7055  0.1 22.2 1564952 225952 pts/3  Sl   09:30   0:04 mysqld --defaults-file=/data/mysql/mysql3308/my3308.cnf --wsrep-new-cluster
root      7661  0.0  0.0 112640   960 pts/0    R+   10:11   0:00 grep --color=auto mysqld

[root@zlm2 10:11:28 ~]
#mysqladmin -uzlm -pzlmzlm -h192.168.1.101 -P3308 shutdown
mysqladmin: [Warning] Using a password on the command line interface can be insecure.

[root@zlm2 10:11:50 ~]
#ps aux|grep mysqld
root      7672  0.0  0.0 112640   960 pts/0    R+   10:12   0:00 grep --color=auto mysqld

[root@zlm2 09:39:30 /data/mysql/mysql3308/data]
#mysqld --defaults-file=/data/mysql/mysql3308/my3308.cnf --wsrep-new-cluster &
[2] 7690
[1]   Done                    mysqld --defaults-file=/data/mysql/mysql3308/my3308.cnf --wsrep-new-cluster

[root@zlm2 10:12:44 /data/mysql/mysql3308/data]
#ps aux|grep mysqld
mysql     7690  5.8 20.6 1556488 210296 pts/3  Sl   10:12   0:01 mysqld --defaults-file=/data/mysql/mysql3308/my3308.cnf --wsrep-new-cluster
root      7729  0.0  0.0 112640   960 pts/3    R+   10:13   0:00 grep --color=auto mysqld

//No ERROR messages were found in error log.

 

 Restart PXC again on zlm3 and check the output of error log.

 1 [root@zlm3 10:27:10 ~]
 2 #ps aux|grep mysqld
 3 root      6694  0.0  0.0 112640   960 pts/1    R+   10:43   0:00 grep --color=auto mysqld
 4 [2]+  Exit 1                  mysqld --defaults-file=/data/mysql/mysql3308/my3308.cnf
 5 
 6 [root@zlm3 10:30:01 /data/mysql/mysql3308/data]
 7 #cat error.log |grep ERROR
 8     2018-08-08T08:27:19.819918Z WSREP_SST: [ERROR] Cleanup after exit with status:1
 9 2018-08-08T10:27:19.826527+01:00 0 [ERROR] WSREP: Process completed with error: wsrep_sst_xtrabackup-v2 --role 'joiner' --address '192.168.1.102' --datadir '/data/mysql/mysql3308/data/' --defaults-file '/data/mysql/mysql3308/my3308.cnf' --defaults-group-suffix '' --parent '6021' --binlog '/data/mysql/mysql3308/logs/mysql-bin' : 1 (Operation not permitted)
10 2018-08-08T10:27:19.826557+01:00 0 [ERROR] WSREP: Failed to read uuid:seqno from joiner script.
11 2018-08-08T10:27:19.826565+01:00 0 [ERROR] WSREP: SST script aborted with error 1 (Operation not permitted)
12 2018-08-08T10:27:19.826592+01:00 0 [ERROR] WSREP: SST failed: 1 (Operation not permitted)
13 2018-08-08T10:27:19.826595+01:00 0 [ERROR] Aborting

 

Check the error log on donor node zlm2 begin with the time of starting mysqld on joiner zlm3.

  1 2018-08-08T10:54:47.539174+01:00 0 [Note] WSREP: (d4006db4, 'tcp://0.0.0.0:4567') connection established to b3de093b tcp://192.168.1.102:4567
  2 2018-08-08T10:54:47.539620+01:00 0 [Note] WSREP: (d4006db4, 'tcp://0.0.0.0:4567') turning message relay requesting on, nonlive peers: 
  3
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