Key Concepts
Partitions
Replication
Retention
Consumer Groups
Required Permissions
How to Create a Topic
Select Kafka Cluster
Click Create Topic
Enter Basic Settings
- Topic Name (required): Unique identifier
- Partitions: Number of partitions (1-1000)
- Replication Factor: Number of replicas (1-10)
Configure Advanced Settings
- Retention (ms): How long to keep messages (-1 for unlimited)
- Cleanup Policy: delete, compact, or both
- Min In-Sync Replicas: Minimum replicas for acks=all
Create
Topic Name Rules
Topic names must follow these rules:Partition Guidelines
How to View Topic Details
Find the Topic
Click to Open
Explore Tabs
- Overview: Partition details, replicas, ISR status
- Messages: Browse and search messages
- Consumers: Consumer groups consuming this topic
- Settings: Topic configuration
How to Browse Messages
Open Topic Detail
Go to Messages Tab
Configure Filters
- Partition: Filter by specific partition
- Offset: Start from a specific offset
- Key Contains: Search by message key
- Value Contains: Search by message value
Browse Results
How to Produce a Message
Open Topic Detail
Go to Messages Tab
Click Produce Message
Enter Message Details
- Key (optional): Message key for partitioning
- Value (required): Message content
- Partition (optional): Target partition (-1 for auto)
- Headers (optional): Key-value metadata
Send
How to Update Topic Configuration
Open Topic Detail
Go to Settings Tab
Modify Configuration
Save Changes
Common Configuration Options
How to Increase Partitions
Open Topic Detail
Go to Settings Tab
Enter New Partition Count
Apply
How to Clear Messages
Clearing messages deletes all data from a topic while keeping the topic itself.Open Topic Detail
Click Clear Messages
Confirm
How to Delete a Topic
Find the Topic
Click Delete
Confirm
How to Use Favorites
Mark frequently used topics as favorites for quick access.Find the Topic
Click the Star
Filter by Favorites
Understanding Partition Details
Each partition displays:Under-Replicated Partitions (URP)
A partition is under-replicated when ISR count < replica count. This indicates:- A broker is down or unreachable
- A replica is falling behind
- Network issues between brokers
Cleanup Policies
When to Use Compact
Use compaction for:- State stores (latest user profile, settings)
- Changelog topics
- Deduplication scenarios
delete.retention.ms to control how long tombstones are retained.Troubleshooting
Topic creation failed
Topic creation failed
- Topic name may already exist
- Invalid characters in topic name
- Replication factor exceeds available brokers
- Cluster may be in maintenance mode
Messages not appearing
Messages not appearing
- Messages may be in a different partition
- Check if you’re looking at the correct offset range
- Consumer may have already committed past these offsets
- Topic may have low retention and messages expired
Cannot produce messages
Cannot produce messages
- You need produce permission
- Topic may be read-only (internal topics)
- Message size may exceed
max.message.bytes - Cluster may be unavailable
Cannot delete topic
Cannot delete topic
- You need delete permission
- Topic may be in use by active consumers
- Cluster’s
delete.topic.enablemay be false
Partition count cannot be decreased
Partition count cannot be decreased
High consumer lag
High consumer lag
- Consumer may be processing slowly
- Consumer group may have fewer members than partitions
- Consider increasing partition count and consumer instances
- Check for processing errors in consumer application
FAQ
What's the difference between partitions and replicas?
What's the difference between partitions and replicas?
How do I choose the right number of partitions?
How do I choose the right number of partitions?
What happens when a broker fails?
What happens when a broker fails?
How does message ordering work?
How does message ordering work?
What is min.insync.replicas?
What is min.insync.replicas?
acks=all). Set to replication_factor - 1 for best availability while maintaining durability.Can I change a topic's replication factor?
Can I change a topic's replication factor?
What are internal topics?
What are internal topics?
_ or __ are internal Kafka topics (like __consumer_offsets, __transaction_state). They’re managed by Kafka and shouldn’t be modified directly. By default, they’re hidden from the topic list.How long are messages retained?
How long are messages retained?
retention.ms (time-based) and retention.bytes (size-based). Messages are deleted when either limit is exceeded. Default is 7 days. Set to -1 for unlimited time-based retention.Best Practices
Naming Conventions
Use consistent naming patterns:Partition Strategy
- Key-based: Messages with same key go to same partition (default)
- Round-robin: No key means random partition assignment
- Custom: Use custom partitioner for special requirements
Production Settings
For production topics:Monitoring
Monitor these metrics:- Under-replicated partitions (should be 0)
- Consumer lag (should be stable or decreasing)
- Message rate (for capacity planning)
- Partition distribution (should be balanced)