Server

Server Commands

Server commands handle connection management, database operations, key management, configuration, introspection, and persistence. This page covers the full set of general-purpose commands.

Connection & General

PING

Synopsis: PING [message]

Test the connection. Returns PONG without arguments, or echoes the given message.

> PING
PONG
> PING "hello"
"hello"

ECHO

Synopsis: ECHO message

Return the given message. Useful for testing.

> ECHO "Hello, rLightning!"
"Hello, rLightning!"

HELLO

Synopsis: HELLO [protover [AUTH username password] [SETNAME clientname]]

Switch the connection to RESP2 or RESP3 protocol, optionally authenticating and setting the client name in a single command.

> HELLO 3
1) "server"
2) "rlightning"
3) "version"
4) "7.0.0"
5) "proto"
6) (integer) 3
...

QUIT

Synopsis: QUIT

Close the connection.

> QUIT
OK

RESET

Synopsis: RESET

Reset the connection state: exit any MULTI/SUBSCRIBE mode, unwatch keys, select DB 0, and clear the client name.

> RESET
+RESET

SELECT

Synopsis: SELECT index

Switch to a different database. rLightning supports 16 databases (0-15) by default.

> SELECT 1
OK

Key Management

KEYS

Synopsis: KEYS pattern

Return all keys matching a glob-style pattern. Use with caution in production — consider SCAN instead.

> SET user:1 "Alice"
OK
> SET user:2 "Bob"
OK
> KEYS user:*
1) "user:1"
2) "user:2"

SCAN

Synopsis: SCAN cursor [MATCH pattern] [COUNT count] [TYPE type]

Incrementally iterate over keys. Returns a cursor for the next call and an array of keys.

> SCAN 0 MATCH user:* COUNT 10
1) "0"
2) 1) "user:1"
   2) "user:2"

EXISTS

Synopsis: EXISTS key [key ...]

Check if one or more keys exist. Returns the count of existing keys.

> SET key1 "hello"
OK
> EXISTS key1 key2
(integer) 1

TYPE

Synopsis: TYPE key

Return the type of value stored at key (string, list, set, zset, hash, stream).

> SET mykey "hello"
OK
> TYPE mykey
string

RENAME

Synopsis: RENAME key newkey

Rename a key. Overwrites newkey if it already exists.

> SET mykey "hello"
OK
> RENAME mykey newkey
OK

RENAMENX

Synopsis: RENAMENX key newkey

Rename a key only if the new key does not already exist. Returns 1 if renamed, 0 otherwise.

> RENAMENX mykey newkey
(integer) 1

DEL

Synopsis: DEL key [key ...]

Delete one or more keys. Returns the number of keys that were removed.

> SET key1 "a"
OK
> SET key2 "b"
OK
> DEL key1 key2 key3
(integer) 2

UNLINK

Synopsis: UNLINK key [key ...]

Delete one or more keys asynchronously. Like DEL but the memory reclamation happens in the background.

> UNLINK key1 key2
(integer) 2

COPY

Synopsis: COPY source destination [DB destination-db] [REPLACE]

Copy the value stored at the source key to the destination key. With REPLACE, overwrites the destination if it exists.

> SET src "hello"
OK
> COPY src dst
(integer) 1
> GET dst
"hello"

RANDOMKEY

Synopsis: RANDOMKEY

Return a random key from the current database.

> RANDOMKEY
"user:42"

TTL & Expiration

EXPIRE

Synopsis: EXPIRE key seconds [NX | XX | GT | LT]

Set a timeout on a key in seconds. Returns 1 if the timeout was set, 0 otherwise.

> SET mykey "hello"
OK
> EXPIRE mykey 60
(integer) 1

EXPIREAT

Synopsis: EXPIREAT key unix-time-seconds [NX | XX | GT | LT]

Set the expiration as a Unix timestamp in seconds.

> EXPIREAT mykey 1893456000
(integer) 1

EXPIRETIME

Synopsis: EXPIRETIME key

Return the absolute Unix timestamp (seconds) at which the key will expire. Returns -1 if the key has no TTL, -2 if the key does not exist.

> EXPIRETIME mykey
(integer) 1893456000

PEXPIRE

Synopsis: PEXPIRE key milliseconds [NX | XX | GT | LT]

Set a timeout on a key in milliseconds.

> PEXPIRE mykey 60000
(integer) 1

PEXPIREAT

Synopsis: PEXPIREAT key unix-time-milliseconds [NX | XX | GT | LT]

Set the expiration as a Unix timestamp in milliseconds.

> PEXPIREAT mykey 1893456000000
(integer) 1

PEXPIRETIME

Synopsis: PEXPIRETIME key

Return the absolute Unix timestamp (milliseconds) at which the key will expire.

> PEXPIRETIME mykey
(integer) 1893456000000

TTL

Synopsis: TTL key

Return the remaining time to live of a key in seconds. Returns -1 if the key has no TTL, -2 if the key does not exist.

> SET mykey "hello"
OK
> EXPIRE mykey 60
(integer) 1
> TTL mykey
(integer) 59

PTTL

Synopsis: PTTL key

Return the remaining time to live of a key in milliseconds.

> PTTL mykey
(integer) 59432

PERSIST

Synopsis: PERSIST key

Remove the expiration from a key, making it persistent. Returns 1 if the timeout was removed, 0 if the key has no TTL.

> EXPIRE mykey 60
(integer) 1
> PERSIST mykey
(integer) 1
> TTL mykey
(integer) -1

Serialization

DUMP

Synopsis: DUMP key

Return a serialized version of the value stored at key. The format is opaque and can be restored with RESTORE.

> SET mykey "hello"
OK
> DUMP mykey
"\x00\x05hello\n\x00..."

RESTORE

Synopsis: RESTORE key ttl serialized-value [REPLACE] [ABSTTL] [IDLETIME seconds] [FREQ frequency]

Create a key from a serialized value produced by DUMP. TTL of 0 means no expiration.

> RESTORE newkey 0 "\x00\x05hello\n\x00..."
OK

Sorting

SORT

Synopsis: SORT key [BY pattern] [LIMIT offset count] [GET pattern [GET pattern ...]] [ASC | DESC] [ALPHA] [STORE destination]

Sort the elements in a list, set, or sorted set. With STORE, saves the result to a destination key.

> RPUSH mylist 3 1 2
(integer) 3
> SORT mylist
1) "1"
2) "2"
3) "3"
> SORT mylist DESC ALPHA
1) "3"
2) "2"
3) "1"

SORT_RO

Synopsis: SORT_RO key [BY pattern] [LIMIT offset count] [GET pattern [GET pattern ...]] [ASC | DESC] [ALPHA]

Read-only variant of SORT (no STORE option). Safe for use on replicas.

> SORT_RO mylist ASC
1) "1"
2) "2"
3) "3"

Object Introspection

OBJECT ENCODING

Synopsis: OBJECT ENCODING key

Return the internal encoding used for the value stored at key.

> SET mykey "hello"
OK
> OBJECT ENCODING mykey
"embstr"
> SET mykey 12345
OK
> OBJECT ENCODING mykey
"int"

OBJECT REFCOUNT

Synopsis: OBJECT REFCOUNT key

Return the reference count of the object stored at key.

> OBJECT REFCOUNT mykey
(integer) 1

OBJECT IDLETIME

Synopsis: OBJECT IDLETIME key

Return the idle time (seconds since last access) of the object stored at key.

> OBJECT IDLETIME mykey
(integer) 5

OBJECT FREQ

Synopsis: OBJECT FREQ key

Return the access frequency of the object stored at key. Only available when the LFU eviction policy is active.

> OBJECT FREQ mykey
(integer) 10

OBJECT HELP

Synopsis: OBJECT HELP

Return help text describing the available OBJECT sub-commands.

> OBJECT HELP
1) "OBJECT <subcommand> [<arg> [value] [opt] ...]. Subcommands are:"
2) "ENCODING <key>"
3) "FREQ <key>"
4) "HELP"
5) "IDLETIME <key>"
6) "REFCOUNT <key>"

Database Operations

DBSIZE

Synopsis: DBSIZE

Return the number of keys in the current database.

> DBSIZE
(integer) 42

FLUSHDB

Synopsis: FLUSHDB [ASYNC | SYNC]

Delete all keys in the current database.

> FLUSHDB
OK

FLUSHALL

Synopsis: FLUSHALL [ASYNC | SYNC]

Delete all keys in all databases.

> FLUSHALL
OK

SWAPDB

Synopsis: SWAPDB index1 index2

Swap two databases atomically. All clients connected to either database will see the other database’s data.

> SWAPDB 0 1
OK

Persistence

SAVE

Synopsis: SAVE

Perform a synchronous RDB save. Blocks the server until complete.

> SAVE
OK

BGSAVE

Synopsis: BGSAVE [SCHEDULE]

Perform a background RDB save. Returns immediately.

> BGSAVE
Background saving started

BGREWRITEAOF

Synopsis: BGREWRITEAOF

Trigger a background AOF rewrite.

> BGREWRITEAOF
Background append only file rewriting started

LASTSAVE

Synopsis: LASTSAVE

Return the Unix timestamp of the last successful RDB save.

> LASTSAVE
(integer) 1678886400

Server Information

INFO

Synopsis: INFO [section [section ...]]

Return information and statistics about the server. Sections include: server, clients, memory, persistence, stats, replication, cpu, modules, keyspace, and all.

> INFO server
# Server
redis_version:7.0.0
...
> INFO memory keyspace
# Memory
used_memory:1048576
...
# Keyspace
db0:keys=42,expires=10,avg_ttl=30000

TIME

Synopsis: TIME

Return the current server time as a two-element array: Unix timestamp in seconds and microseconds.

> TIME
1) "1678886400"
2) "123456"

LOLWUT

Synopsis: LOLWUT [VERSION version]

Display the rLightning version in a fun way.

> LOLWUT
rLightning ver. 1.0.0
...

Configuration

CONFIG GET

Synopsis: CONFIG GET parameter [parameter ...]

Get the value of one or more configuration parameters. Supports glob-style patterns.

> CONFIG GET maxmemory
1) "maxmemory"
2) "0"
> CONFIG GET max*
1) "maxmemory"
2) "0"
3) "maxmemory-policy"
4) "noeviction"

CONFIG SET

Synopsis: CONFIG SET parameter value [parameter value ...]

Set one or more configuration parameters at runtime.

> CONFIG SET maxmemory 256mb
OK
> CONFIG SET maxmemory-policy allkeys-lru
OK

CONFIG RESETSTAT

Synopsis: CONFIG RESETSTAT

Reset the statistics reported by INFO (e.g., keyspace hits/misses, total commands processed).

> CONFIG RESETSTAT
OK

CONFIG REWRITE

Synopsis: CONFIG REWRITE

Rewrite the configuration file to reflect the current in-memory configuration.

> CONFIG REWRITE
OK

Command Introspection

COMMAND COUNT

Synopsis: COMMAND COUNT

Return the total number of commands supported by the server.

> COMMAND COUNT
(integer) 400

COMMAND DOCS

Synopsis: COMMAND DOCS [command-name [command-name ...]]

Return documentation for the specified commands.

> COMMAND DOCS GET
1) "GET"
2) 1) "summary"
   2) "Get the value of a key"
   ...

COMMAND INFO

Synopsis: COMMAND INFO [command-name [command-name ...]]

Return detailed information about the specified commands including arity, flags, and key positions.

> COMMAND INFO GET SET
1) 1) "get"
   2) (integer) 2
   3) 1) "readonly"
      2) "fast"
   ...

COMMAND LIST

Synopsis: COMMAND LIST [FILTERBY MODULE module-name | ACLCAT category | PATTERN pattern]

List all commands, optionally filtered by module, ACL category, or pattern.

> COMMAND LIST FILTERBY ACLCAT string
1) "append"
2) "get"
3) "set"
...

COMMAND GETKEYS

Synopsis: COMMAND GETKEYS command [arg ...]

Extract the keys from a command without executing it.

> COMMAND GETKEYS SET mykey myvalue
1) "mykey"
> COMMAND GETKEYS MSET k1 v1 k2 v2
1) "k1"
2) "k2"

Client Management

CLIENT LIST

Synopsis: CLIENT LIST [TYPE NORMAL | MASTER | REPLICA | PUBSUB] [ID client-id [client-id ...]]

Return information about connected clients.

> CLIENT LIST
id=1 addr=127.0.0.1:54321 fd=5 name= db=0 ...

CLIENT GETNAME

Synopsis: CLIENT GETNAME

Return the name of the current connection, or nil if no name is set.

> CLIENT GETNAME
(nil)

CLIENT SETNAME

Synopsis: CLIENT SETNAME connection-name

Set the name of the current connection for identification in CLIENT LIST.

> CLIENT SETNAME myapp-worker-1
OK

CLIENT ID

Synopsis: CLIENT ID

Return the unique ID of the current connection.

> CLIENT ID
(integer) 42

CLIENT INFO

Synopsis: CLIENT INFO

Return information about the current client connection.

> CLIENT INFO
id=42 addr=127.0.0.1:54321 ...

CLIENT KILL

Synopsis: CLIENT KILL [ID client-id | ADDR ip:port | LADDR ip:port | USER username | SKIPME yes | no | MAXAGE seconds]

Close client connections matching the specified filters. Returns the number of clients killed.

> CLIENT KILL ID 42
(integer) 1

CLIENT NO-EVICT

Synopsis: CLIENT NO-EVICT ON | OFF

Set the client eviction mode. When ON, the client will not be evicted even under memory pressure.

> CLIENT NO-EVICT ON
OK

Monitoring & Debugging

SLOWLOG

Synopsis: SLOWLOG GET [count] | SLOWLOG LEN | SLOWLOG RESET

Manage the slow queries log.

> SLOWLOG GET 2
1) 1) (integer) 1
   2) (integer) 1678886400
   3) (integer) 15000
   4) 1) "SORT"
      2) "mylist"
> SLOWLOG LEN
(integer) 5
> SLOWLOG RESET
OK

DEBUG

Synopsis: DEBUG subcommand [argument]

Server debugging commands. Not intended for production use.

> DEBUG SLEEP 0.5
OK
> DEBUG SET-ACTIVE-EXPIRE 0
OK

LATENCY

Synopsis: LATENCY LATEST | LATENCY HISTORY event | LATENCY RESET [event ...]

Monitor and analyze server latency events.

> LATENCY LATEST
(empty array)

Memory

MEMORY USAGE

Synopsis: MEMORY USAGE key [SAMPLES count]

Return the memory usage in bytes of a key and its value.

> SET mykey "hello"
OK
> MEMORY USAGE mykey
(integer) 56

MEMORY STATS

Synopsis: MEMORY STATS

Return detailed memory consumption statistics.

> MEMORY STATS
 1) "peak.allocated"
 2) (integer) 1048576
 3) "total.allocated"
 4) (integer) 524288
 ...

MEMORY DOCTOR

Synopsis: MEMORY DOCTOR

Return memory diagnostic advice.

> MEMORY DOCTOR
"Sam, I have no memory problems"

MEMORY MALLOC-STATS

Synopsis: MEMORY MALLOC-STATS

Return the memory allocator’s internal statistics.

> MEMORY MALLOC-STATS
(allocator stats output)

Replication & Sync

WAIT

Synopsis: WAIT numreplicas timeout

Block until all preceding write commands are acknowledged by at least numreplicas replicas, or the timeout (ms) expires. Returns the number of replicas that acknowledged.

> SET mykey "hello"
OK
> WAIT 1 5000
(integer) 1

Lifecycle

SHUTDOWN

Synopsis: SHUTDOWN [NOSAVE | SAVE] [NOW] [FORCE]

Shut down the server. With SAVE, triggers an RDB save before shutting down. With NOSAVE, shuts down without saving.

> SHUTDOWN SAVE
(server exits)

Module System

MODULE LIST

Synopsis: MODULE LIST

List all loaded modules.

> MODULE LIST
(empty array)

MODULE LOAD

Synopsis: MODULE LOAD path [arg ...]

Load a module from the given path.

> MODULE LOAD /path/to/module.so
OK

MODULE UNLOAD

Synopsis: MODULE UNLOAD name

Unload a module by name.

> MODULE UNLOAD mymodule
OK