一次获取国内源失败，导致配置丢失。 wrong or NULL argument passed，解决办法是重置manjaro的mirro 源

1.报错如下

[shenfeng@Flame ~]$ sudo pacman -Sy
error: could not add server URL to database 'core':  (wrong or NULL argument passed)
error: could not add server URL to database 'extra':  (wrong or NULL argument passed)
error: could not add server URL to database 'community':  (wrong or NULL argument passed)
error: could not add server URL to database 'multilib':  (wrong or NULL argument passed)
:: Synchronizing package databases...
error: failed retrieving file 'core.db' from mirrors.163.com : The requested URL returned error: 404

2.让manjaro 帮我们找最快的一个

sudo pacman-mirrors --fasttrack 

3.然后

sudo pacman -Sy

附--参考文档---https://wiki.manjaro.org/index.php?title=Pacman-mirrors