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Questions tagged [replication]

The use of redundant resources to improve reliability, fault-tolerance, or performance.

Replication is the process of sharing information so as to ensure consistency between redundant resources, such as software or hardware components, to improve reliability, fault-tolerance, or accessibility.

It could be data replication if the same data is stored on multiple storage devices, or computation replication if the same computing task is executed many times.

A computational task is typically replicated in space, i.e. executed on separate devices, or it could be replicated in time, if it is executed repeatedly on a single device.

The access to a replicated entity is typically uniform with access to a single, non-replicated entity. The replication itself should be transparent to an external user. Also, in a failure scenario, a failover of replicas is hidden as much as possible.

More info on Wikipedia

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MySQL: Very slow update/insert/delete queries hanging on "query end" step

I have a large and heavy loaded mysql database which performs quite fast at times, but some times get terribly slow. All tables are InnoDB, server has 32GB of RAM and database size is about 40GB. Top 20 queries in my slow_query_log are update,…
Silver Light
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Data Replication error in Hadoop

I am implementing the Hadoop Single Node Cluster on my machine by following Michael Noll's tutorial and have come across data replication error: Here's the full error message: > hadoop@laptop:~/hadoop$ bin/hadoop dfs -copyFromLocal > tmp/testfiles…
Apoorv Saxena
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MySQL replication Error 'You cannot 'ALTER' a log table if logging is enabled' on query

MySQL replication got broken with the last error being Last_Errno: 1580 Last_Error: Error 'You cannot 'ALTER' a log table if logging is enabled' on query. Default database: 'mysql'. Seems this is the fault of running mysql_upgrade for version…
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How to know MySQL replication status using a select query?

Is it possible to get replication status from any system database table? Using which I can identify whether the replication is up or down. I need to to know whether the SLAVE_IO_RUNNING and SLAVE_SQL_RUNNING = YES from a system table.
MySQL DBA
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Replicate a single table

Is it possible to replicate a single table?
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Can you replicate a specific database or table using Amazon's RDS

We are using Amazon RDS and we have a MASTER replicating to a SLAVE. We want to create a new slave that will only replicate specific databases or tables from the master. By default RDS simply just replicates the entire master's databases over to…
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MySQL replication: if I don't specify any databases, will log_bin log EVERYTHING?

I'm setting up replication for a server which runs a bunch of databases (one per client) and plan on adding more all the time, on my.cnf, Instead of having: binlog-do-db = databasename 1 binlog-do-db = databasename 2 binlog-do-db = databasename…
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Keeping distributed databases synchronized in a unstable network

I'm facing the following challenge: I have a bunch of databases in different geographical locations where the network may fail a lot (I'm using cellular network). I need to keep all the databases synchronized but there is no need to be in real time.…
jassuncao
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manually create replication slot for publication in PostgreSQL 10

I am trying to get a stream of updates for certain tables from my PostgreSQL database. The regular way of getting all updates looks like this: You create a logical replication slot pg_create_logical_replication_slot('my_slot', 'wal2json'); And…
George
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Is it safe to delete replication relay-bin files?

I've got a small database, around 50mb. It's a master replicating to a remote server. I noticed that the relay-bin files total to over 5GB. Is it safe to delete them?
HyderA
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Full complete MySQL database replication? Ideas? What do people do?

Currently I have two Linux servers running MySQL, one sitting on a rack right next to me under a 10 Mbit/s upload pipe (main server) and another some couple of miles away on a 3 Mbit/s upload pipe (mirror). I want to be able to replicate data on…
mauriciopastrana
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How do I check SQL replication status via T-SQL?

I want to be able to check the status of a publication and subscription in SQL Server 2008 T-SQL. I want to be able to determine if its okay, when was the last successful, sync, etc.. Is this possible?
user17222
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Muzak replication advice and techniques

I am attempting my first large scale database project on my own. I have a myisam mysql db on server 1 with a php app consuming large amount of various data. I have mysql myisam on server 2 with php app selecting and displaying data. I want to…
user915831
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Zookeeper/Chubby -vs- MySql NDB

I have been reading the Paxos paper, the FLP theorem etc. recently and evaluating Apache Zookeeper for a project. I have also been going thru Chubby (Google's distributed locking service) and the various literature on it that is available online. My…
arun_suresh
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How to achieve read/write separation with Entity Framework

I have a database setup using 'master/slave replication'. I have one master and (at least) one slave, possibly ℕ slaves. For simplicity from here on I'll talk about one master, one slave because determining which slave to use includes some…
RobIII
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