Cassandra Top 20 DBA Day to Day Task List | 2024
4 min readMar 19, 2024
- Cassandra Cluster Setup: Setting up a Cassandra cluster involves configuring multiple nodes or systems to work together as a distributed database system. This can be done manually by configuring each node individually or automatically using tools or scripts to streamline the process. In this task list, the setup involves three nodes or instances, each contributing to the overall cluster’s storage and processing capacity.
- Vertical Scaling Up: Vertical scaling refers to increasing the capacity of individual nodes in the cluster. This can be achieved by upgrading the AWS (Amazon Web Services) instance types associated with each node. Upgrading instance types typically provides more CPU, memory, and storage resources, allowing the cluster to handle increased workloads more efficiently.
- Vertical Scaling Down: Conversely, vertical scaling down involves reducing the capacity of individual nodes in the cluster. This might be necessary to optimize costs or adjust to changes in workload demands. Scaling down typically involves downgrading the AWS instance types associated with each node to lower-cost options that still meet the cluster’s requirements.
- Horizontal Scaling Up: Horizontal scaling involves increasing the number of nodes in the cluster to distribute the workload across more instances. Adding nodes to an existing cluster can improve performance and scalability by allowing the system to handle more concurrent requests and store larger volumes of data.
- Horizontal Scaling Down: Similarly, horizontal scaling down involves removing nodes from the cluster. This might be necessary to reduce costs, simplify management, or optimize resource utilization in response to changes in workload patterns.
- Create/Alter DB/Keyspace: In Cassandra, a keyspace is analogous to a database schema in traditional relational databases. Creating or altering a keyspace involves defining the high-level structure and configuration parameters for storing related data tables. In this task, the keyspace named ‘empdb’ is created or modified to accommodate the specific requirements of the application or use case.
- DDL and DML Operations: Data Definition Language (DDL) and Data Manipulation Language (DML) operations are fundamental to managing database objects and manipulating data within Cassandra. DDL includes commands for creating, altering, and dropping tables, while DML encompasses operations such as inserting, updating, deleting, and querying data.
- Authentication and Authorization: Ensuring secure access to the Cassandra cluster involves enabling authentication and authorization mechanisms. PasswordAuthenticator is used for authentication, requiring users to provide valid credentials to access the database, while CassandraAuthorizer is used for authorization, controlling user privileges and access rights to database objects.
- User Management: Managing user accounts involves creating new users with specific permissions and privileges and deleting existing users when necessary. User management tasks help control access to the database and ensure that only authorized individuals can interact with sensitive data.
- Grant/Revoke Permissions: Granting and revoking permissions allows administrators to fine-tune access control settings for individual users or groups. By granting specific permissions (e.g., read, write, modify) to certain users or roles and revoking permissions as needed, administrators can enforce security policies and restrict access to sensitive data.
- Repair Tasks: Data repair tasks are essential for maintaining data consistency and integrity within the Cassandra cluster. Full repairs, primary range repairs, keyspace repairs, and table repairs address various types of data inconsistencies and are automated using scripts or tools like the Cassandra Reaper to streamline maintenance operations.
- Compaction: Compaction is the process of consolidating and optimizing data storage within Cassandra to improve performance and reduce disk space usage. Full compaction, keyspace compaction, and table-level compaction tasks are scheduled and automated to run at specified intervals, ensuring optimal database performance.
- Handling Storage Failure: Handling storage failures involves implementing strategies to minimize data loss and restore data integrity in the event of hardware or storage system failures. Nodetool repair and nodetool rebuild are utilized to repair data inconsistencies and recover data from backups in scenarios of varying data loss severity.
- Backup Strategies: Backup strategies are crucial for protecting against data loss and ensuring disaster recovery preparedness. Methods such as using the COPY command, taking snapshots at the cluster, keyspace, and table levels, and leveraging tools like DSBULK for large datasets are employed to create backups that can be restored as needed.
- Restoration: Restoration tasks involve restoring data from backups to recover lost or corrupted data in the event of data loss or system failures. Various methods, including COPY commands and sstableloader, are used for cluster, keyspace, and table-level restores to ensure data integrity and availability.
- Data Migration: Data migration tasks involve transferring data between environments or data centers. Exporting data using COPY commands, transferring data files, and importing data into target environments facilitate seamless data migration processes while ensuring data consistency and integrity.
- Monitoring: Monitoring the Cassandra cluster involves tracking various performance metrics and system health indicators to ensure optimal operation and identify potential issues proactively. OS monitoring tools and Cassandra-specific monitoring commands provide insights into system resource utilization, node availability, request throughput, and latency.
- Alerting and Log Analysis: Alerting mechanisms and log analysis help detect and respond to critical events or anomalies in the Cassandra cluster. By setting up alerts for predefined thresholds or conditions and analyzing system logs, administrators can promptly address issues and prevent service disruptions or data loss.
