Server Commands

Server commands provide control over Redis server operations, configuration, persistence, and monitoring.

INFO

Returns information and statistics about the server.

Syntax

INFO [section [section ...]]

section

string

Specific section(s) to return. Omit for all sections. Available sections:

server: General server information
clients: Client connections
memory: Memory usage
persistence: RDB and AOF information
stats: General statistics
replication: Master/replica information
cpu: CPU consumption
commandstats: Command statistics
cluster: Redis Cluster information
keyspace: Database key statistics
modules: Loaded modules
errorstats: Error statistics

info

string

Server information in key:value format, organized by sections.

Time Complexity: O(1) History:

7.0.0: Added support for taking multiple section arguments.

Examples

redis> INFO server
# Server
redis_version:7.0.0
redis_mode:standalone
os:Linux 5.10.0 x86_64
arch_bits:64
tcp_port:6379
uptime_in_seconds:3600

redis> INFO memory
# Memory
used_memory:1024000
used_memory_human:1000.00K
used_memory_peak:2048000
used_memory_peak_human:2.00M

redis> INFO stats
# Stats
total_connections_received:100
total_commands_processed:5000
instantaneous_ops_per_sec:150

CONFIG

Manages Redis server configuration.

Syntax

CONFIG GET parameter
CONFIG SET parameter value [parameter value ...]
CONFIG REWRITE
CONFIG RESETSTAT

parameter

string

required

Configuration parameter name. Supports glob patterns for CONFIG GET.

value

string

required

Value to set for the parameter.

result

array

For GET: Array of parameter-value pairs. For SET: OK on success. For REWRITE: OK on success. For RESETSTAT: OK on success.

Time Complexity: O(N) for CONFIG GET where N is the number of configuration parameters requested. O(1) for CONFIG SET.

Examples

redis> CONFIG GET maxmemory
1) "maxmemory"
2) "1073741824"

redis> CONFIG GET max*
1) "maxmemory"
2) "1073741824"
3) "maxclients"
4) "10000"
5) "maxmemory-policy"
6) "noeviction"

redis> CONFIG SET maxmemory 2147483648
OK

redis> CONFIG REWRITE
OK

redis> CONFIG RESETSTAT
OK

SAVE

Synchronously saves the dataset to disk.

Syntax

SAVE

result

string

OK on success.

Time Complexity: O(N) where N is the total number of keys in all databases.

SAVE blocks the server until the save is complete. For production use, prefer BGSAVE which saves in the background.

Examples

redis> SAVE
OK
# Server is blocked during save operation

SHUTDOWN

Synchronously saves the dataset and shuts down the server.

Syntax

SHUTDOWN [NOSAVE | SAVE] [NOW] [FORCE] [ABORT]

SAVE

option

Force a DB saving operation even if no save points are configured.

NOSAVE

option

Prevent DB saving operation even if save points are configured.

NOW

option

Skip waiting for replicas to catch up.

FORCE

option

Ignore errors during shutdown.

ABORT

option

Cancel ongoing shutdown.

result

none

No response - server shuts down. Returns error if ABORT is used or shutdown fails.

Time Complexity: O(N) where N is the total number of keys when saving.

Examples

redis> SHUTDOWN SAVE
# Server saves and shuts down

redis> SHUTDOWN NOSAVE
# Server shuts down without saving

FLUSHDB

Deletes all keys in the current database.

Syntax

FLUSHDB [ASYNC | SYNC]

ASYNC

option

Delete keys asynchronously in a background thread.

SYNC

option

Delete keys synchronously (blocks server).

result

string

OK on success.

Time Complexity: O(N) where N is the number of keys in the database.

Examples

redis> SET key1 "value1"
OK
redis> SET key2 "value2"
OK
redis> FLUSHDB
OK
redis> DBSIZE
(integer) 0

redis> FLUSHDB ASYNC
OK

Additional Server Commands

BGSAVE: Background save
LASTSAVE: Get timestamp of last successful save
BGREWRITEAOF: Rewrite AOF file in background
DBSIZE: Get number of keys in current database
FLUSHALL: Delete all keys in all databases
MEMORY: Memory diagnostics
SLOWLOG: Slow query log
MONITOR: Monitor all commands in real-time
CLIENT: Manage client connections
COMMAND: Get command information
TIME: Get server time
PING: Test connection
ECHO: Echo message
QUIT: Close connection
ROLE: Get replication role
REPLICAOF: Set replication source
SYNC: Internal replication command
PSYNC: Partial resynchronization
DEBUG: Debugging utilities
MODULE: Manage Redis modules
ACL: Access control lists
LATENCY: Latency monitoring

Use Cases

Health Monitoring

Check server health:

# Check if server is alive
redis> PING
PONG

# Get server statistics
redis> INFO stats
# Stats
total_connections_received:1000
total_commands_processed:50000

# Check memory usage
redis> INFO memory
# Memory
used_memory:10485760
used_memory_human:10.00M

Performance Tuning

Optimize configuration:

# Check current settings
redis> CONFIG GET maxmemory-policy
1) "maxmemory-policy"
2) "noeviction"

# Update for better performance
redis> CONFIG SET maxmemory-policy allkeys-lru
OK

# Set memory limit
redis> CONFIG SET maxmemory 2gb
OK

# Persist changes
redis> CONFIG REWRITE
OK

Backup Operations

Create database backups:

# Background save (non-blocking)
redis> BGSAVE
Background saving started

# Check last save time
redis> LASTSAVE
(integer) 1640000000

# Check if save is in progress
redis> INFO persistence
# Persistence
rdb_bgsave_in_progress:0
rdb_last_save_time:1640000000

Client Management

Manage connections:

# List connected clients
redis> CLIENT LIST
id=1 addr=127.0.0.1:52500 name= age=10 idle=0
id=2 addr=127.0.0.1:52501 name=worker age=20 idle=5

# Kill specific client
redis> CLIENT KILL 127.0.0.1:52501
OK

# Set client name
redis> CLIENT SETNAME myapp
OK

# Get client name
redis> CLIENT GETNAME
"myapp"

Slow Query Analysis

Identify slow commands:

# Get slow log entries
redis> SLOWLOG GET 10
1) 1) (integer) 14
   2) (integer) 1640000000
   3) (integer) 15000
   4) 1) "GET"
      2) "key"
   5) "127.0.0.1:52500"
   6) "client"

# Get slow log length
redis> SLOWLOG LEN
(integer) 128

# Reset slow log
redis> SLOWLOG RESET
OK

Best Practices

Configuration Management

Use CONFIG REWRITE to persist changes
Test configuration changes in development
Monitor memory usage after changes
Document configuration decisions

Persistence Strategy

RDB (Snapshots)
AOF (Append Only)
Hybrid

Point-in-time snapshots:

# Configure automatic saves
redis> CONFIG SET save "900 1 300 10 60 10000"
OK

# Manual save
redis> BGSAVE
Background saving started

Pros: Compact, fast restarts Cons: Data loss between saves

Log every write:

# Enable AOF
redis> CONFIG SET appendonly yes
OK

# Set sync policy
redis> CONFIG SET appendfsync everysec
OK

# Rewrite AOF
redis> BGREWRITEAOF
Background append only file rewriting started

Pros: More durable, minimal data loss Cons: Larger files, slower restarts

Use both RDB and AOF:

redis> CONFIG SET save "900 1"
OK
redis> CONFIG SET appendonly yes
OK

Pros: Best durability, fast restarts Cons: More disk I/O

Monitoring

Regular health checks:

# Memory usage alert
redis> INFO memory | grep used_memory_human

# Command statistics
redis> INFO commandstats
# Commandstats
cmdstat_get:calls=1000,usec=5000,usec_per_call=5.00
cmdstat_set:calls=500,usec=3000,usec_per_call=6.00

# Check for errors
redis> INFO errorstats

Patterns

Graceful Shutdown

Shutdown with data preservation:

# Ensure data is saved
redis> BGSAVE
Background saving started

# Wait for save to complete
redis> INFO persistence | grep rdb_bgsave_in_progress

# Shutdown gracefully
redis> SHUTDOWN SAVE

Configuration Rollback

Revert configuration changes:

# Save original value
redis> CONFIG GET maxmemory
1) "maxmemory"
2) "1073741824"

# Make change
redis> CONFIG SET maxmemory 2147483648
OK

# Test and rollback if needed
redis> CONFIG SET maxmemory 1073741824
OK

Maintenance Mode

Enter maintenance mode:

# Stop accepting writes
redis> CONFIG SET min-replicas-to-write 1
OK
redis> CONFIG SET min-replicas-max-lag 0
OK

# Perform maintenance

# Resume normal operation
redis> CONFIG SET min-replicas-to-write 0
OK

Memory Pressure Response

Handle memory pressure:

# Check memory usage
redis> INFO memory

# If near limit, enable eviction
redis> CONFIG SET maxmemory-policy allkeys-lru
OK

# Or increase limit
redis> CONFIG SET maxmemory 4gb
OK

Server Information

Key INFO sections:

Server Section

redis> INFO server
# Server
redis_version:7.0.0
redis_mode:standalone
os:Linux 5.10.0 x86_64
process_id:12345
tcp_port:6379
uptime_in_seconds:86400
uptime_in_days:1

Memory Section

redis> INFO memory
# Memory
used_memory:10485760
used_memory_human:10.00M
used_memory_peak:20971520
used_memory_peak_human:20.00M
mem_fragmentation_ratio:1.25

Stats Section

redis> INFO stats
# Stats
total_connections_received:10000
total_commands_processed:500000
instantaneous_ops_per_sec:1000
total_net_input_bytes:104857600
total_net_output_bytes:209715200
rejected_connections:0

Replication Section

redis> INFO replication
# Replication
role:master
connected_slaves:2
slave0:ip=10.0.1.10,port=6379,state=online
slave1:ip=10.0.1.11,port=6379,state=online

FLUSHDB and FLUSHALL are destructive operations that delete all data. Always use with caution and consider using ASYNC option to avoid blocking.

Command Statistics

Analyze command usage:

redis> INFO commandstats
# Commandstats
cmdstat_get:calls=10000,usec=50000,usec_per_call=5.00
cmdstat_set:calls=5000,usec=40000,usec_per_call=8.00
cmdstat_del:calls=1000,usec=5000,usec_per_call=5.00

# Reset statistics
redis> CONFIG RESETSTAT
OK

Debugging

Debug server issues:

# Monitor all commands
redis> MONITOR
OK
1640000000.123456 [0 127.0.0.1:12345] "GET" "key"
1640000000.123789 [0 127.0.0.1:12346] "SET" "key" "value"

# Get server time
redis> TIME
1) "1640000000"
2) "123456"

# Check latency
redis> LATENCY DOCTOR

Commands

Modules API

Protocol

Documentation Index

​INFO

​Syntax

​Examples

​CONFIG

​Syntax

​Examples

​SAVE

​Syntax

​Examples

​SHUTDOWN

​Syntax

​Examples

​FLUSHDB

​Syntax

​Examples

​Related Commands

​Additional Server Commands

​Use Cases

​Health Monitoring

​Performance Tuning

​Backup Operations

​Client Management

​Slow Query Analysis

​Best Practices

​Configuration Management

​Persistence Strategy

​Monitoring

​Patterns

​Graceful Shutdown

​Configuration Rollback

​Maintenance Mode

​Memory Pressure Response

​Server Information

​Server Section

​Memory Section

​Stats Section

​Replication Section

​Command Statistics

​Debugging

INFO

Syntax

Examples

CONFIG

Syntax

Examples

SAVE

Syntax

Examples

SHUTDOWN

Syntax

Examples

FLUSHDB

Syntax

Examples

Related Commands

Additional Server Commands

Use Cases

Health Monitoring

Performance Tuning

Backup Operations

Client Management

Slow Query Analysis

Best Practices

Configuration Management

Persistence Strategy

Monitoring

Patterns

Graceful Shutdown

Configuration Rollback

Maintenance Mode

Memory Pressure Response

Server Information

Server Section

Memory Section

Stats Section

Replication Section

Command Statistics

Debugging