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MySQL NDB Cluster Backup & Restore In An Easy Way

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In this post, we will see, how easily user can take NDB Cluster backup and then restore it. NDB cluster supports online backups, which are taken while transactions are modifying the data being backed up. In NDB Cluster, each backup captures all of the table content stored in the cluster. User can take backup in the following states: When the cluster is live and fully operational When the cluster is live, but in a degraded state: Some data nodes are down Some data nodes are restarting During read and write transactions Users can restore backups in the following cluster environments: Restore to the same physical cluster Restore into a different physical cluster Restore into a different configuration cluster i.e. backup taken from a 4 nodes cluster and restore into 8 data nodes cluster Restore into a different cluster version Backups can be restored flexibly: Restore can be run locally or remotely w.r.t the data nodes Restore can be run in parallel across data nodes Can restore a partial

MySQL Cluster Self Healing And No Single Point Of Failure Feature

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In this post we will see the unique features of MySQL Cluster i.e. Self healing and no single point of failure. MySQL Cluster No Single Point Of Failure: As we know that in MySQL Cluster, data nodes are logically grouped into nodegroups. All data nodes in a nodegroup contain the same data, kept in sync at all times. Different nodegroups contain different data. So in a single nodegroup, MySQL Cluster can sustain multiple node shutdown at the same time but at least one node must live in that nodegroup. Lets demonstrate this feature with a 4 replicas cluster where each nodegroup have 4 data nodes. Lets create a MySQL Cluster with below environment. MySQL Cluster 8.0.22 version 2 Management servers 8 Data nodes servers 2 Mysqld servers 4 API nodes OS: Ubuntu 20.04 LTS NoOfReplicas = 4 Lets check the cluster status from the management client: We can see that 8 nodes cluster is up and running with 4 replicas. Also we can see that each nodegroup has 4 data nodes. Lets kill two data nodes from

Cluster Installation On Physical Hosts:

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In this post, we will see how easily we can install MySQL Cluster on different physical hosts. One can install MySQL Cluster on a single host too. If you are wondering what MySQL Cluster is then please look into my previous post. MySQL Cluster Installation : Lets create a MySQL Cluster with the following environment: MySQL Cluster 8.0.22 version 2 Management servers 4 Data nodes servers 2 Mysqld servers 4 API nodes OS: Ubuntu 20.04 LTS Hostname and IP address of all the nodes in the MySQL  Cluster: Management Node1 (mgmt1):           Hostname: cluster-test01,  IP: 100.103.21.121 Management Node2 (mgmt2):           Hostname: cluster-test02,  IP: 100.103.21.131 Data Node1: Hostname: cluster-test03, IP: 100.103.21.126 Data Node2: Hostname: cluster-test04, IP: 100.103.21.129 Data Node3: Hostname: cluster-test05, IP: 100.103.21.130 Data Node4: Hostname: cluster-test06, IP: 100.103.21.125 Mysqld Server 1 (mysqld1):                        Hostname: cluster-test07, IP: 100.103.21.137 Mysqld Se