导读：Redis是一个高性能的Key-Value数据库，它支持多种类型的日志记录。本文将介绍如何开启redis的日志类型，并且详细解释每种类型的作用和使用方法。
1. 开启普通日志
在redis.conf文件中，找到以下配置项：
# Specify the log file name. Also the empty string can be used to force
# Redis to log on the standard output. Note that if you use standard
# output for logging but daemonize, logs will be sent to /dev/null
# logging to the standard output is bad for performance but can be useful
# for debugging.
logfile ""
将其修改为：
logfile "/var/log/redis.log"
即可开启redis的普通日志功能，所有redis的操作都会被记录在/var/log/redis.log文件中。
2. 开启慢查询日志
# The threshold for slow commands is a time in microseconds, and affects
# only Redis commands that have a linear complexity (i.e. O(N) or worse),
# so it is not very useful for commands that are more complex in nature
# (i.e. O(log N)).
slowlog-log-slower-than 10000
slowlog-max-len 128
将slowlog-log-slower-than配置项设置为一个正整数，表示执行时间超过该阈值的命令将被记录在慢查询日志中。slowlog-max-len配置项表示慢查询日志的最大长度，当达到该长度时，旧的记录将被覆盖。
3. 开启RDB持久化日志
# The filename where to dump the DB
dbfilename dump.rdb
# The working directory.
#
# The DB will be written inside this directory, with the filename specified
# above using the 'dbfilename' configuration directive.
# The Append Only File will also be created inside this directory.
dir ./
将dbfilename配置项设置为一个文件名，表示RDB持久化日志将被记录在该文件中。dir配置项表示RDB和AOF文件的保存路径。
4. 开启AOF持久化日志
# Append only mode
appendonly no
# The name of the append only file
appendfilename "appendonly.aof"
# The fsync() call tells the Operating System to actually write data on disk
# instead of waiting for more data in the output buffer. Some OS will really flush
# data on disk, some other OS will just try to do it ASAP.
# Redis supports three different modes:
# no: don't fsync, just let the OS flush the data when it wants. Faster.
# always: fsync after every write to the append only log. Slow, Safest.
# everysec: fsync only one time every second. Compromise.
appendfsync everysec
将appendonly配置项设置为yes，表示开启AOF持久化日志功能。appendfilename配置项表示AOF文件的保存路径。appendfsync配置项表示AOF文件的写入频率，可以选择不写入、每次写入、或者每秒写入一次。
总结：Redis支持多种类型的日志记录，包括普通日志、慢查询日志、RDB持久化日志和AOF持久化日志。开启这些日志类型可以帮助开发人员更好地了解Redis的运行情况，以及出现问题时进行调试和排查。
