Baradb/docs/en/troubleshooting.md

Troubleshooting Guide

Installation Issues

Nim Not Found

im: command not found

Solution:

# Linux/macOS
curl https://nim-lang.org/choosenim/init.sh -sSf | sh

# Add to PATH
echo 'export PATH=$HOME/.nimble/bin:$PATH' >> ~/.bashrc
source ~/.bashrc

SSL Compilation Error

Error: BaraDB requires SSL support. Compile with -d:ssl

Solution: Always compile with -d:ssl:

nim c -d:ssl -d:release -o:build/baradadb src/baradadb.nim

Missing Dependencies

Error: cannot open file: hunos

Solution:

nimble install -d -y

Runtime Issues

Port Already in Use

Error: unhandled exception: Address already in use [OSError]

Solution 1: Change port:

BARADB_PORT=5433 ./build/baradadb

Solution 2: Kill existing process:

lsof -ti:5432 | xargs kill -9
# or
fuser -k 5432/tcp

Permission Denied on Data Directory

Error: cannot create directory: Permission denied

Solution:

mkdir -p ./data
chmod 755 ./data
# Or use a different directory
BARADB_DATA_DIR=/tmp/baradb_data ./build/baradadb

Out of Memory

Error: out of memory

Solution: Reduce memory usage:

BARADB_MEMTABLE_SIZE_MB=32 \
BARADB_CACHE_SIZE_MB=128 \
BARADB_VECTOR_EF_CONSTRUCTION=100 \
./build/baradadb

Disk Full

Error: No space left on device

Solution:

# Check disk usage
df -h

# Trigger compaction to reclaim space
curl -X POST http://localhost:8080/api/admin/compact

# Or manually
./build/baradadb --compact

Query Issues

Syntax Error

Error: Syntax error at position 15: unexpected token

Solution: Check query syntax:

-- Correct
SELECT name, age FROM users WHERE age > 18;

-- Incorrect (missing comma)
SELECT name age FROM users WHERE age > 18;

Table Not Found

Error: Table 'users' does not exist

Solution: Create the schema first:

CREATE TYPE User {
  name: str,
  age: int32
};

Type Mismatch

Error: Cannot compare int32 with str

Solution: Use correct types:

-- Correct
SELECT * FROM users WHERE age > 18;

-- Incorrect
SELECT * FROM users WHERE age > '18';

Timeout

Error: Query execution timeout

Solution: Add LIMIT or optimize:

-- Add limit
SELECT * FROM large_table LIMIT 1000;

-- Use index
SELECT * FROM users WHERE id = 123;

Connection Issues

Connection Refused

Connection refused: localhost:5432

Solution:

# Check if server is running
ps aux | grep baradadb

# Start server
./build/baradadb

# Check firewall
sudo ufw status
sudo ufw allow 5432

Authentication Failed

Error: Authentication failed

Solution:

# Check JWT secret matches
BARADB_AUTH_ENABLED=true \
BARADB_JWT_SECRET="correct-secret" \
./build/baradadb

client.authenticate("correct-jwt-token")

SSL/TLS Errors

Error: TLS handshake failed

Solution:

# Disable TLS for local testing
BARADB_TLS_ENABLED=false ./build/baradadb

# Or provide valid certificates
BARADB_TLS_ENABLED=true \
BARADB_CERT_FILE=/path/to/cert.pem \
BARADB_KEY_FILE=/path/to/key.pem \
./build/baradadb

Performance Issues

Slow Queries

Diagnose:

# Check query plan
curl -X POST http://localhost:8080/api/explain \
  -d '{"query": "SELECT * FROM large_table"}'

Solutions:

1. Add indexes:

CREATE INDEX idx_users_name ON users(name);

2. Use LIMIT:

SELECT * FROM users LIMIT 100;

3. Increase cache:

BARADB_CACHE_SIZE_MB=1024 ./build/baradadb

High CPU Usage

Causes:

• Compaction running
• Large vector search without HNSW
• Complex graph traversal

Solutions:

# Adjust compaction interval
BARADB_COMPACTION_INTERVAL_MS=300000 ./build/baradadb

# Use approximate vector search
SELECT /*+ APPROXIMATE */ * FROM vectors
ORDER BY cosine_distance(embedding, [...])
LIMIT 10;

High Memory Usage

Monitor:

curl http://localhost:8080/metrics | grep memory

Solutions:

# Reduce memtable size
BARADB_MEMTABLE_SIZE_MB=64

# Reduce cache
BARADB_CACHE_SIZE_MB=256

# Limit HNSW graph size
BARADB_VECTOR_M=8

Cluster Issues

Raft Split-Brain

Warning: Multiple leaders detected

Solution: Ensure odd number of nodes (3, 5, 7). Restart minority partition.

Replication Lag

Warning: Replication lag > 10s

Solution:

# Check network latency
ping replica-node

# Increase replication threads
BARADB_REPLICATION_THREADS=4 ./build/baradadb

# Switch to async replication
BARADB_REPLICATION_MODE=async

Shard Imbalance

Warning: Shard 3 has 2× data of others

Solution:

# Trigger rebalancing
curl -X POST http://localhost:8080/api/admin/rebalance

Data Corruption

Checksum Mismatch

Error: SSTable checksum mismatch

Solution:

# Remove corrupted SSTable (data will be recovered from WAL)
rm ./data/sstables/corrupted.sst

# Restart and recover
./build/baradadb --recover

WAL Corruption

Error: WAL segment corrupted

Solution:

# Truncate WAL to last good segment
./build/baradadb --truncate-wal --wal-sequence=15419

# Restore from snapshot if needed
./build/baradadb --recover --checkpoint=/backup/snapshot.db

Debug Mode

Enable debug logging for detailed diagnostics:

BARADB_LOG_LEVEL=debug \
BARADB_LOG_FILE=/tmp/baradb_debug.log \
./build/baradadb

Getting Help

If the issue persists:

1. Check logs: tail -f /var/log/baradb/baradb.log
2. Check metrics: curl http://localhost:8080/metrics
3. Run diagnostics: ./build/baradadb --diagnose
4. Open an issue with:
   • BaraDB version (./build/baradadb --version)
   • OS and architecture
   • Relevant log excerpts
   • Steps to reproduce