本文内容为 http://redis.io/commands/config-rewrite 的翻译、注解、例子扩充及其它修改。感谢 Redis 作者 Antirez 为开源社区作出的贡献,本文保证最新、最准、最全以表示对其的敬意。欢迎留言纠错、提示更新或支持。
CONFIG REWRITE

该命令会重写用于启动当前服务端的 redis.conf 配置文件。

The CONFIG REWRITE command rewrites the redis.conf file the server was started with, applying the minimal changes needed to make it reflecting the configuration currently used by the server, that may be different compared to the original one because of the use of the CONFIG SET command.
The rewrite is performed in a very conservative way:
  • Comments and the overall structure of the original redis.conf are preserved as much as possible.
  • If an option already exists in the old redis.conf file, it will be rewritten at the same position (line number).
  • If an option was not already present, but it is set to its default value, it is not added by the rewrite process.
  • If an option was not already present, but it is set to a non-default value, it is appended at the end of the file.
  • Non used lines are blanked. For instance if you used to have multiple save directives, but the current configuration has fewer or none as you disabled RDB persistence, all the lines will be blanked.
CONFIG REWRITE is also able to rewrite the configuration file from scratch if the original one no longer exists for some reason. However if the server was started without a configuration file at all, the CONFIG REWRITE will just return an error.

Atomic rewrite process

In order to make sure the redis.conf file is always consistent, that is, on errors or crashes you always end with the old file, or the new one, the rewrite is perforemd with a single write(2) call that has enough content to be at least as big as the old file. Sometimes additional padding in the form of comments is added in order to make sure the resulting file is big enough, and later the file gets truncated to remove the padding at the end.
  • 当配置被正常写入时,返回 OK

    否则,将会返回一个错误。

    Simple string reply: OK when the configuration was rewritten properly. Otherwise an error is returned.
  • 版本支持

    2.8.0+