MemSQL After installation

After basic installation of MemSQL, Now we need to understand the important parameters that effects the cluster. The three main parameters that affects the cluster are

• durability
• redundancy_level
• master-aggregator

The above three parameters should be added in master aggregator at /var/lib/memsql/memsql.cnf and after adding the above parameters restart the server using "service memsql restart" command

USE & IMPACTS

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• durability : - This is very important feature of MemSQL. If this is on then MemSQL takes periodic snapshot and log changes to disk and if its off then it will save only metadata to disk. This is the beauty of MemSQL that your data is secure on disk as well as available in-memory for high-availability. 

• redundancy_level : - To add redundancy to the database we can set redundancy_level which means data is available in separate groups called availability groups which contains a copy of every partition in the system- some as masters and some as slaves. Currently MemSQL supports two level of redundancy level 1 and 2 which means each partition of database on master has a copy of slave on other leaf.

• master-aggregator : - MemSQL is actually two tiered clustered architecture which has two types of server. Aggregator and the Leaves. Aggregators are the nodes which acts as mediator between client request and the cluster nodes (leaves). Aggregators only contains metadata and the leaves contains actual data. Aggregators are of two types Master and the Child aggregaors. To make master aggregator one should have change in memsql.cnf file is "master-aggregator" and restart the MemSQL.

TO BE CONTINUED............................