Automatic failover of Moodle database in PostgreSQL using ClusterControl

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, , , failover, (promote) . failover Moodle PostgreSQL ClusterControl.

failover 

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• uptime

  
  
  
  
  

• DBA ,

  
  
  
  
  

 

Postgres — HAProxy, Moodle PostgreSQL. failover ClusterControl (cluster recovery) (node auto recovery).

ClusterControl , failover.

cmon :

1. replication_failover_whitelist
   
   
   
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2. replication_failover_blacklist
   
   
   
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(auto failover)

1

(192.168.33.14) sysbench.

[root@centos11 sysbench]# /bin/sysbench --db-driver=pgsql --oltp-table-size=100000 --oltp-tables-count=24 --threads=2 --pgsql-host=****** --pgsql-port=6543 --pgsql-user=sbtest --pgsql-password=***** --pgsql-db=sbtest /usr/share/sysbench/tests/include/oltp_legacy/parallel_prepare.lua run
 
sysbench 1.0.20 (using bundled LuaJIT 2.1.0-beta2)
 
 
 
Running the test with following options:
 
Number of threads: 2
 
Initializing random number generator from current time
 
 
 
 
Initializing worker threads...
 
 
 
Threads started!
 
 
 
thread prepare0
 
Creating table 'sbtest1'...
 
Inserting 100000 records into 'sbtest1'
 
Creating secondary indexes on 'sbtest1'...
 
Creating table 'sbtest2'...
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

2

Postgres (192.168.33.14). ClusterControl enable_cluster_autorecovery, .

# service postgresql-12 stop
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

3

ClusterControl . , .

192.168.33.13 , . HAProxy Moodle . 

192.168.33.13

postgres=# select pg_is_in_recovery();
 
 pg_is_in_recovery 
 
-------------------
 
 f
 
(1 row)
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

192.168.33.15

postgres=# select pg_is_in_recovery();
 
 pg_is_in_recovery 
 
-------------------
 
 t
 
(1 row)
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

HAProxy . , ClusterControl.

ClusterControl , HAProxy , .

, . ClusterControl. , , .

ClusterControl .

failover — Moodle. , . , failover .

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"PostgreSQL".

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