Revision of last five classes
- We have started our discussion with relational databases
- Different ways of creating Databases in AWS
- IAAS approach:
- Creating an ec2 instance with necessary os
- install database management system (mysql, postgres, oracle, db2, microsoft sql server)
- Import data and use it
- PAAS approach:
- AWS has a service called as RDS (Relational Database Services) which helps in creating
- mysql
- mariadb
- postgres
- sql server
- oracle
- In this case we just need to manage the data import and data inside database
- AWS has a service called as RDS (Relational Database Services) which helps in creating
- IAAS approach:
- Databases are created in VPC’s. AWS allows users to create db subnet group to select the subnets where db can be launched
- AWS also allows users to create a db security group which acts as firewall around database
- Databases in RDS can be
- Multi-AZ
- Single-AZ
- AWS RDS allows us to create read replica of the rds instance in the same region or in different region.
- AWS RDS read replica can be promoted to become primary database where the write operations also will be allowed.
- Backups of the AWS RDS can be selected by choosing the retention period. Backups are referred as snapshots.
- AWS RDS offers two kinds of connectivities
- Publicly accesible
- Private connectivity
- SSH Tunneling connections are also available
- When we create dbs we need to select the instance class
- Standard
- Memory Optimized
- Burstable
- Storage:
- Three storage types
- General purpose ssd
- provisioned iops
- Magnetic (standard)
- Limitations:
- upto 64 TiB for mysql, maria db, oracle and postgres
- upto 16 TiB for Microsoft SQl Server
- Three storage types
- Purchasing Options
- On-demand:
- No-Commitments
- Will be charge as you use hourly
- Costlier option
- Reservered
- 1-year or 3-year commitment with AWS
- Suitable for production workloads
- Will recieve discount upto 59%
- On-demand:
Backups of RDS Databases
- Backup options while creating an rds instance
- Create an rds instance with any db engine (mysql) with 7 days of backup
- In this case aws will automatically take backups
- Users can also initiate on-demand backups
- Once the Snapshot is created, we can copy snapshot, share snapshot, export the snapshot to s3 bucket
- From snapshot we can create a database by restoring snapshot.
- Snapshots are the better way to share data in databases with other AWS Users
