Two or more dots in your relay log or binary log names can break replication; but worry not, it will only do it once. If you request to start again,…
The post Relay log read failure | 2 many dots can break your replication only once first appeared on Change Is Inevitable.
MySQL 8.0.23 introduces a new feature that makes replication possible from a source server that has been configured without Global Transaction Identifiers (GTIDs) to a replica server configured with GTIDs. This can be achieved by configuring replication channels to use the parameter ASSIGN_GTIDS_TO_ANONYMOUS_TRANSACTIONS with the CHANGE REPLICATION SOURCE command.…
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In this blog, we will discuss about how to setup MySQL NDB
Cluster replication in a more secure way with the help of binary
log and relay log encryption and a secure connection. These
measures protect binary log dat in transit and at rest.
Let’s create two MySQL NDB Clusters with the following
environment, Here, one will be termed as ‘source’ cluster and the
other one will be termed as ‘replica’ cluster.
Step 1: Start both of the Clusters
Let’s start both the source cluster and replica cluster but do
not start the MySQLD servers from both the clusters as we want to
modify their configuration first.
…
In this blog, we will discuss, how to setup MySQL NDB Cluster
replication through backup and restore method. This is bit
tricky but interesting. The scenario here is, say user have a
standalone cluster up and running, later there is a need to have
a replication setup with an another empty cluster without
shutting down the existing running cluster i.e. zero downtime.
Then this backup and restore method will come in handy.
Let’s create two MySQL NDB Cluster with the following
environment, Here, one will be termed as ‘source’ cluster and the
other one will be termed as ‘replica’ cluster.
Replication schema diagram:
CLUSTER
'A' …
In this blog, we will discuss about bidirectional
replication between two NDB clusters. With this topology,
user can do transaction simultaneously from both the clusters on
the same database objects.
Let’s create two MySQL NDB Cluster with the following
environment, Here, both will be termed as ‘source’ cluster as
well as ‘replica’ cluster as we will do replication from both the
sides.
Replication schema diagram:
|-----------S1---------->>----------S3--------------|
…
In the previous blog, we were able to setup a MySQL NDB Cluster
replication between one source and one replica cluster. In this
blog, we will discuss about replication between one source and
three replica clusters.
Note: With MySQL version (8.0.21), we have started
changing the term “master” to “source”, the term “slave” to
“replica”. So in this blog we will refer these terms ‘source’ and
‘replica’ wherever applicable.
The main advantage of this type of topology is good for giving
‘local’ reads in geographically distant areas as well as
increased redundancy in case of issues.
Let’s create four MySQL NDB Cluster with the following
environment, from which one will be termed as ‘source’ cluster
while the rest will be ‘replica’ clusters.
In this blog series, we will discuss various MySQL NDB Cluster
replication topologies possible with a demonstration. We will
start with a simple case i.e. one source (formerly called master)
and one replica (formerly called slave).
Note: With MySQL version (8.0.21), we have started changing the
term “master” to “source”, the term “slave” to “replica”. So in
this blog we will refer these terms ‘source’ and ‘replica’
wherever applicable.
Let’s create two MySQL NDB Cluster with the following
environment, from which one will be termed as ‘source’ cluster
while the other one will be ‘replica’ cluster. For now, let’s
stick to the identical environment from both the cluster. Later
in the following blog series, we will change the environments and
will run the replication.
MySQL InnoDB Cluster is the High Availability solution for MySQL.
It delivers automatic fail-over and guarantees zero data loss
(RPO=0).
RPO: Recovery Point Objective describes the interval of time that might pass during a disruption before the quantity of data lost during that period exceeds the Business Continuity Plan’s maximum allowable tolerance.
Example: our business architecture needs to have RPO=2 minutes. This means that in case of failure, 2 minutes of data can be lost.
However, and we saw this recently in Europe, an entire data center can “disappear” instantaneously… So it’s also important to have a Disaster Recovery plan.
One solution, is to have an InnoDB Cluster (Group Replication) that spans across multiple regions. However, this is often not feasible because of high latency across regions.
Another solution is InnoDB Cluster in one region with Asynchronous …
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From MySQL 5.7, we had a Multi-threaded Slave (MTS) Applier
mechanism called
LOGICAL_CLOCK to overcome the
problems of parallel replication within a database.
To further improve the parallelisation mechanism, from MySQL 8 (5.7.22) we have write-set replication, so before going further , lets look at the difference between Logical clock (LC) and Writeset.
LOGICAL_CLOCK
Transactions that are part of the same binary log group commit on a master are applied in parallel on a slave. The dependencies between transactions are tracked based on their timestamps to provide additional parallelisation where possible.
WRITESET
Write-set is a mechanism to track independent
transactions that can be executed in parallel in the slave.
Parallelising on write sets has potentially much more parallelism
than logical_clock ,since it does not depend …
MySQL Replication is a very common topology, widely used in
various architecture.
People use it, among others, for High Availability, Read
Scalability or Geographic Redundancy.
Another use case is to use MySQL Replication to seamlessly
integrate a newer version of the server in your
architecture.
Let’s say you are running MySQL 5.7 then you can easily setup a
8.0 instance as a replica of your 5.7.
Extending this idea it is also possible to replicate your MySQL 5.7 (or 8.0 obviously) to a MySQL Database Service instance, the true MySQL PaaS on Oracle Cloud Infrastructure.
The post Replicate from MySQL 5.7 to MySQL Database Service first appeared on dasini.net - Diary of a MySQL experts.