Proves it is correct. Measures that it is fast.

INFO, without the fiction

Sections that carry only what the node can state: no resident-set figure it would have to guess, no fork it does not have.

# Memory
maxmemory_policy:allkeys-lru
# Persistence
loading:0
aof_enabled:1
fsync_policy:interval
aof_last_write_status:ok
refusing_executors:0

One JSON line per event

Every line opens with a time, a level and the event's name; a monitor selects by evt and reads fields by name, with no parser of its own.

{"ts":1757800000000,"level":"info","evt":"listening","version":"0.1.1","bind":"0.0.0.0","port":6379}
{"ts":1757800000317,"level":"warn","evt":"error_reply","code":"ERR","cmd":"flushall","msg":"ERR unknown command 'flushall'"}

A password that rotates without a restart

Two passwords are valid while the file holds two, so the server and its clients never have to change in the same moment.

1. 1add the new line, SIGHUP
2. 2move the clients, any pace
3. 3drop the old line, SIGHUP

{"ts":1757800003250,"level":"info","evt":"password_reloaded","passwords":2}

A disk that fails is met with refusal

A write the node cannot keep is not acknowledged: writes are refused until a snapshot is durable, reads are served, and a full disk asks for space, not for a restart.

# the disk is full, --fsync always
> SET order:9 paid
-MISCONF Errors writing to the log: writes are refused until a snapshot is durable
# space freed, a snapshot durable: refusal_ended
> SET order:9 paid
+OK