WAITAOF

WAITAOF waits until every write this connection made so far is in an append-only file (AOF) on disk: on this server when numlocal is 1, and on at least numreplicas replicas. It returns as soon as both are true, or when timeout milliseconds pass, and reports how far it got either way.

When the AOF reaches the disk depends on appendfsync: at once with always, within about a second with everysec, and only at the next rewrite with no. Each replica follows its own appendfsync. With everysec, a short timeout can run out before the fsync, so give it a second or more.

The connection is blocked while it waits; other clients are served as usual. Inside MULTI or a script, WAITAOF replies at once with the current state.

Options

Argument	Meaning
numlocal	1 to wait for this server’s AOF, 0 not to. Needs appendonly yes when 1.
numreplicas	How many replicas must have the writes in their AOF on disk.
timeout	Milliseconds to wait at most. 0 waits as long as it takes.

Return value

An array of two integers, in RESP2 and RESP3:

1. 1 if this server’s AOF on disk has the writes, else 0 (always 0 with the AOF off).
2. The number of replicas whose AOF on disk has them.

Error case	Error
numlocal not an integer	ERR value is not an integer or out of range
numlocal not 0 or 1	ERR value is out of range, value must between 0 and 1
numreplicas not a non-negative integer	ERR value is out of range, must be positive
timeout not an integer	ERR timeout is not an integer or out of range
timeout negative	ERR timeout is negative
Sent to a replica	ERR WAITAOF cannot be used with replica instances. Please also note that writes to replicas are just local and are not propagated.
numlocal 1 with the AOF off	ERR WAITAOF cannot be used when numlocal is set but appendonly is disabled.

Examples

127.0.0.1:6379> SET invoice:77 "issued"
OK
127.0.0.1:6379> WAITAOF 1 1 1000
1) (integer) 1
2) (integer) 1

Compatibility

Same arguments, replies and errors as Redis 7.2 and later, and Valkey 8.

See also

WAIT, BGREWRITEAOF, persistence

In a cluster: Replicas and failover