What is Redis CLI?

redis-cli is the command-line interface for Redis, the in-memory data structure store used as a cache, message broker, and database. Mastering redis-cli is essential for debugging cache issues, performance analysis, and Redis administration.

Connection

# Connect to local Redis
redis-cli

# Connect to remote Redis
redis-cli -h redis.example.com -p 6379 -a your_password

# Connect with TLS
redis-cli -h redis.example.com -p 6380 --tls --cacert /path/to/ca.crt

# Connect to specific database (0-15)
redis-cli -n 3

# Run a single command
redis-cli GET mykey
redis-cli HGETALL user:123

Essential Data Structure Commands

Strings (Caching)

# Set with expiry (TTL in seconds)
SET user:token:abc123 "user_data_here" EX 3600

# Get value
GET user:token:abc123

# Set only if not exists (distributed locks)
SET lock:resource "worker-1" NX EX 30

# Atomic increment
INCR page:views:2026-04-02
INCRBY user:credits:123 100

# Bulk operations
MSET key1 val1 key2 val2 key3 val3
MGET key1 key2 key3

Hashes (Objects)

# Store user object
HSET user:123 name "Alice" email "[email protected]" active 1

# Get all fields
HGETALL user:123

# Get specific field
HGET user:123 email

# Check field exists
HEXISTS user:123 email

# Get all keys/values
HKEYS user:123
HVALS user:123

Lists (Queues)

# Push to queue (FIFO)
LPUSH jobs:pending job1 job2 job3
RPOP jobs:pending  # Process next job

# Blocking pop (wait up to 5 seconds)
BRPOP jobs:pending 5

# List range
LRANGE jobs:pending 0 -1  # All items
LLEN jobs:pending

Sets (Unique Collections)

# Session management
SADD user:123:sessions "session_abc"
SISMEMBER user:123:sessions "session_abc"  # Check membership
SMEMBERS user:123:sessions                  # All sessions
SREM user:123:sessions "session_abc"

# Set operations
SUNION set1 set2  # Union
SINTER set1 set2  # Intersection
SDIFF set1 set2   # Difference

Sorted Sets (Leaderboards)

# Add scores
ZADD leaderboard 1500 "alice"
ZADD leaderboard 2000 "bob"
ZADD leaderboard 1750 "charlie"

# Get ranked list (ascending)
ZRANGE leaderboard 0 -1 WITHSCORES

# Top 3 (descending)
ZREVRANGE leaderboard 0 2 WITHSCORES

# Get rank
ZREVRANK leaderboard "alice"  # 0-indexed rank

# Score for member
ZSCORE leaderboard "alice"

Streams (Event Log)

# Append to stream
XADD events:purchases * user_id 123 amount 99.99 item "laptop"

# Read from stream
XREAD COUNT 10 STREAMS events:purchases 0

# Consumer groups (distributed processing)
XGROUP CREATE events:purchases workers $ MKSTREAM
XREADGROUP GROUP workers consumer1 COUNT 1 STREAMS events:purchases >
XACK events:purchases workers <message-id>

Monitoring and Performance

# Real-time monitoring of commands
redis-cli MONITOR

# Latency histogram
redis-cli --latency-history -i 1  # Every 1 second

# Memory usage
redis-cli MEMORY USAGE user:123  # Bytes used by a key
redis-cli INFO memory             # Full memory stats

# Slow log
redis-cli SLOWLOG GET 10    # Last 10 slow commands
redis-cli SLOWLOG LEN       # Number of slow log entries

# Server info
redis-cli INFO all
redis-cli INFO keyspace

# Find keys matching pattern (use SCAN, not KEYS in production!)
redis-cli SCAN 0 MATCH "user:*" COUNT 100

# Count keys
redis-cli DBSIZE

Key Management

# TTL
redis-cli TTL key            # Remaining TTL in seconds (-1 = no expiry, -2 = doesn't exist)
redis-cli PTTL key           # TTL in milliseconds
redis-cli EXPIRE key 3600   # Set expiry
redis-cli PERSIST key        # Remove expiry

# Key type
redis-cli TYPE key

# Delete
redis-cli DEL key1 key2
redis-cli UNLINK key1 key2  # Async delete (non-blocking for large keys)

# Rename
redis-cli RENAME oldkey newkey

# Check exists
redis-cli EXISTS key

Pipeline Mode (Bulk Operations)

# Execute many commands efficiently
redis-cli --pipe << 'EOF'
SET key1 value1
SET key2 value2
HSET user:1 name Alice email [email protected]
EXPIRE user:1 3600
EOF

Pub/Sub

# Terminal 1: Subscribe
redis-cli SUBSCRIBE channel:updates

# Terminal 2: Publish
redis-cli PUBLISH channel:updates "Hello subscribers!"

# Subscribe to pattern
redis-cli PSUBSCRIBE "events:*"

redis-cli combined with RedisInsight (GUI) gives complete visibility into your Redis deployment.

Redis CLI — Command-Line Interface for Redis

✅ Pros

⚠️ Cons