Questions tagged [master-slave-replication]
The master-slave-replication tag has no usage guidance.
164
questions
11
votes
2answers
25k views
Trying to understand SHOW SLAVE STATUS in MySQL
I have a Master-Slave replication setup and it looks like that it is running fine. Below is a result of SHOW SLAVE STATUS command:
show slave STATUS\G;
*************************** 1. row *************...
5
votes
3answers
4k views
MySQL Master/Slave replication on same VM instance?
I'm fairly new to databases so I hope this isn't a silly question!
Is it possible to set up master/slave replication on the SAME server?
I understand there are not any advantages to this in terms of ...
4
votes
2answers
16k views
PostgreSQL service start failed on CentOS 7
Installed PostgreSQL using:
sudo yum install postgresql-server postgresql-contrib
PostgreSQL version: 9.2.18
When start service:
sudo service postgresql start
Got error:
Redirecting to /bin/...
4
votes
0answers
1k views
Queries running very slowly in Amazon RDS PostgreSQL read-replica
We have been maintaining a project which has both web and mobile application platform. The backend of the project is developed in Django 1.10 and deployed in AWS.
At the beginning, when there were ...
4
votes
1answer
509 views
Can PostgreSQL slave server act as master for a new database?
My question is somewhat related to:
https://stackoverflow.com/questions/19331577/does-postgres-replication-native-support-per-database-level-replication
We have master-slave replication set up on ...
3
votes
3answers
1k views
In replication A->B->C, can A be binlog_format=STATEMENT and B be binlog_format=ROW?
I have replication setup between an on-prem MySQL 5.6 server (A) to another on-prem MySQL 5.6 server (B). I was setting up an AWS DMS instance (C) that I wanted to migrate and then replicate. It ...
3
votes
2answers
3k views
MySQL slave not able to execute long running update query
I am running a Master-slave replication servers of MySQL. As part of clean up of old data, i ran a delete query which deletes huge number of records from the database. It ran fine on Master server but ...
3
votes
2answers
189 views
MySQL chain replication timing of writes on first slave
With a MySQL chain replication setup, e.g. M1->S1->S2, what exactly is the order of operations for writing to the first slave? Is the binary log from the master simply streamed directly through ...
3
votes
1answer
410 views
Why does mysqldump stop the slave SQL thread for the entire backup?
I realized recently that I was using --master-data to dump a backup from a replication slave when what I really wanted was --dump-slave. After switching to --dump-slave, I see that mysqldump will stop ...
3
votes
0answers
398 views
Replication doesn't resume once it fails to connect
We have MySQL replication running for our application. Right now the slave fails to resume if it fails to connect to the server for some time.
We get the error below:
[ERROR] Slave I/O: error ...
3
votes
2answers
44 views
How do I create a MySQL slave server of a bunch of MyISAM databases on a master
I have a MySQL master server and slave became corrupt because of space issues on the master. Binary logs are potentially corrupt and I don't trust them. The databases are using MyISAM tables.
I want ...
3
votes
0answers
6k views
Slave is not configured or failed to initialize properly. You must at least set --server-id to enable either a master or a slave
I am trying to setup multi source replication. In my slave I have defined following two properties in its configuration file.
master-info-repository=table
relay-log-info-repository=table
These ...
2
votes
2answers
2k views
Post Mortem Analysis: PostgreSQL replication failed
We have a PostgreSQL 9.4.9 production server which was replicating to a slave instance, but today I discovered that the instance is out of sync!
The obvious actions would be to recreate the slave, ...
2
votes
2answers
4k views
org.postgresql.util.PSQLException: ERROR: canceling statement due to conflict with recovery
I currently have a PostgreSQL slave node that is presenting problems, that don't arise in the master node. Seems to be related with the node sync process.
Complete stacktrace:
org.postgresql.util....
2
votes
1answer
82 views
Options for having same tables in 2 different data bases
I need to know what options I have for my next problem:
I have 2 databases (sql server 2012)
first for an ERP
second for an website
For the website's database, I want to use a table (customer) ...
2
votes
1answer
1k views
How does one scale out with master-slave replication?
To my understanding, a master-slave replication might be set up where clients can read from multiple databases. However, they can only write to the master. I believe this helps guarantee ACIDity.
I ...
2
votes
1answer
373 views
Master-slave replication doesn't work on PostgreSQL 9.6
I tried to create a master/slave configuration with two servers and Postgres 9.6
I modified master and slave postgresql.conf in /etc/postgresql/9.6/main
Same for master and slave:
data_directory = '...
2
votes
1answer
798 views
MySQL Replication binary relay logs transfer too slowly
Master server
MySQL 5.6.28
Ubuntu 14.04
8 core CPU
Slave server
Slave: MySQL 5.7.22
Ubuntu 18.04
16 core CPU
Both of them have 64GB of RAM and plenty of disk space.
What I did up to this ...
2
votes
1answer
2k views
Can I use MariaDB as a replication slave for MySQL?
I've been a MySQL user/administrator for many years and I've been considering a switch to MariaDB. We have a statement-replicated setup with a MySQL slave and I've been thinking that one way to ease-...
2
votes
1answer
1k views
how can be changed hot_standby parameter on postgres 9.6 aws/rds?
I have a postgres solution on aws/rds with a master and a read replica.
master slave
hot_standby on on
transaction_read_only on on
...
2
votes
1answer
290 views
Fetch just inserted data in master/slave model?
Say I have MySQL master DB(used for updates) and corresponding Slave DB(used for reads). Now user inserts the data into MASTER through application(java), just after insertion he tries to retrieve the ...
2
votes
1answer
392 views
PostgreSQL replication not working after base backup
Last week we had an incident with our master PostgreSQL server instance which got totally thrashed so, we had to switch to our slave as our one and only DB instance. After the initial chaos was ...
2
votes
0answers
23 views
How I can find out which postgresql I am connected into when behind a load balancer?
I have the following database replication setup:
As you can see I do a master-slave replication and I use aload balancer in order to connect into read-only replicas.
So I want to test this setup, ...
2
votes
2answers
259 views
Change user password on slave
Our users can only access the slave database.
How can I let them change their passwords on their own or when their passwords expire?
2
votes
0answers
147 views
How to get the Slave commit timestamp using MySql replication?
I've been looking for ways to collect information about the replication delays on MySql 8. I found an alternative solution, but I imagine there's a more straightforward way to do that.
By reading its ...
2
votes
1answer
333 views
Mongodb replica set primary and secondary node conf fail when one slave is down
In my env, I had created MongoDB replica set conf for high availability so one server fails should be handled by other also in my conf I have 3 DB server and 1 arbiter too but,
my slave's server ...
2
votes
1answer
104 views
Can I stop replication of create/drop index statement on one slave of Mysql 5.6?
I have this cluster where master and slave uses same indexes but one of the slaves has some extra indexes (large machine which runs some analytics queries).
So I have to maintain two sets of indexes. ...
2
votes
0answers
509 views
Cluster using docker
We are creating a new application using microservices, and for that we would like to be able to raise database instances just like we raise new instances for the application's microservices. We do not ...
2
votes
2answers
1k views
Importing a large mysql dump while replication is running
So we have a simple master/slave mysql replication running between two CentOS Servers.
The master has multiple databases. eg..
Database1
Database2
Database3
The issue is we have a mysql dumpfile ...
2
votes
0answers
61 views
Fault tolerant cross datacenter MySQL replication & failover strategy [duplicate]
Which of the following method is the most fault tolerant way to achieve cross datacenter MySQL replication using DNS failover and why?
MySQL master-master replication with one primary/active node and ...
1
vote
3answers
1k views
Select from slave and insert into master in MySQL
Because of pressure on my servers and variety of applications on my servers I was wonder if can I have application or proxy to select from slave database and insert into master.
I'm using PHP/Laravel ...
1
vote
1answer
24 views
Is it possible to configure pgbouncer to distribute queries among master and slave?
We have master (write-read) and slave (readonly) Postgres 10 databases. Slave is online replication from master.
Now our application (c# webapi) connects to master only directly. We want to execute ...
1
vote
1answer
1k views
MySQL Replication Slave Status OK but Data inconsistent
We are using MySQL 5.7, and have a Master and 3 Slave servers replication setup. All the 4 servers are dedicated for MySQL use only, and belong to the same data-center, connected over Private Network. ...
1
vote
1answer
43 views
Does pg_export_snapshot work across replicas?
This is probably of little importance, but it's possible in PostgreSQL to retrieve the transaction snapshot with pg_export_snapshot and restore it with set transaction to start a second transaction ...
1
vote
1answer
69 views
Howto reliably ship WAL log files between master and slave
I have a replication master and a slave on two different computers. Actually both databases are running in docker containers, and their WAL archive directories are exposed to the host machine using ...
1
vote
3answers
602 views
Seconds_Behind_Master high even though Read_Master_Log_Pos and Exec_Master_Log_Pos are very close
From what I understand from https://dev.mysql.com/doc/refman/5.7/en/show-slave-status.html, seconds_behind_master is the difference in the timestamp of where the IO thread is currently writing in the ...
1
vote
2answers
788 views
Need help with Master Slave Replication
I want to set up a Master-Slave Replication. Therefore I followed the MySQL manual. Once I was I wanted to test it. I've let me show the slave status with was as following;
Slave_IO_State: Waiting ...
1
vote
2answers
64 views
MYSQL DATABASE BACKUP
Currently my backup strategy invloves :-
1)I have one master server and two slaves (Data approximately 700 GBs and tables are of mixed innodb and myisam).
2)I take weekly and monthly backup from ...
1
vote
1answer
3k views
How does trigger file in recovery.conf work?
Can someone explain how the trigger_file in recovery.conf works?
As far as I know the standby server will become the primary server when it detects the trigger_file. But how will the trigger_file be ...
1
vote
1answer
25 views
Percona 5.7.24 : How to fix disk slave storage full
I find that my slave disk is full, but I don't understand what makes it full.
Can anyone help me explain what this file is?
And how it is formed, so that it makes lots of files that make storage full.
...
1
vote
1answer
42 views
Master mysq8 slave Mariadb 10.3 Error 22
Master (mysql Ver 8.0.16)
Slaventer code heree (mysql Ver 15.1 Distrib 10.3.15-MariaDB)
I have this error
Error 'Character set '#255' is not a compiled character set and is not specified in the '/...
1
vote
1answer
600 views
MySQL replication works but slave keeps reconnecting to master
I have a master-slave set-up with multiple slaves in different datacenters. One of the slaves stopped working normally today. This was easily resolved by restarting mysqld but ever since (and perhaps ...
1
vote
1answer
78 views
Master-Slave semi circle replication not working in MySQL
I didn't know how to describe it so I am calling it semi circle. Here's what I am doing.
Server A
Server B = This is slave of Server A
Server C = This is slave of Server B
When I update something ...
1
vote
3answers
34 views
Mysql master-slave config in my.cnf
I'm following this guide to setting up a master-slave config (https://support.rackspace.com/how-to/set-up-mysql-master-slave-replication/) and i'm confused about the end of the document where they are ...
1
vote
0answers
19 views
RESET MASTER; does not reset GTID_EXECUTED
I'm trying to get replication up and running between two kubernetes pods, and am getting the dreaded @@GLOBAL.GTID_PURGED can only be set when @@GLOBAL.GTID_EXECUTED is empty. error.
root@central-vm:~...
1
vote
1answer
33 views
MySQL 5.7 Can slave be ahead of master during replication
From my understanding, once commit() is received from client, transactions are written to binlog first before any commit is done to InnoDB.
In this case, is it possible for slaves to be ahead of ...
1
vote
2answers
34 views
Split read/write requests over different read/write datasources
Recently I have run some performance tests on the application I work on, and it turns out that it didn't do really well ( the problem is mainly between the back and the DB). So as investigating the ...
1
vote
1answer
200 views
Issue with Time Zone while migrating MySQL on-premises DB to AWS RDS
I am having MySQL 5.6 database with PST time format in on-premises server. Now we are willing to migrate the database to RDS.
For this, we have taken backup from physical server and restored in RDS ...
1
vote
1answer
252 views
global foreign_key_checks = 0 on RBR slave
Example schema:
CREATE SCHEMA account;
CREATE TABLE `user` (
`id` INT(11) NOT NULL AUTO_INCREMENT,
`name` VARCHAR(50) NULL DEFAULT NULL,
`address` VARCHAR(50) NULL DEFAULT NULL,
...
1
vote
1answer
130 views
PostgreSQL - Replica Recovery Process Stuck frequently (epoll_wait taking too much time)
We have Master Slave Setup with Asynchronous Streaming Replication (Replication Slots). Frequently our Replica's entire Postgres processes seems to be doing nothing (or stuck?). Since ...
