It seems that cnssuestc mirror can only be only accessed by http connection but not https. So I think Server = https://mirrors.cnssuestc.org/archlinuxcn/$arch should be changed to Server = http://mirrors.cnssuestc.org/archlinuxcn/$arch, or ask @KaseiWang or @pandada8 to add https support to this mirror.
It seems that cnssuestc mirror can only be only accessed by http connection but not https. So I think
Server = https://mirrors.cnssuestc.org/archlinuxcn/$arch
should be changed toServer = http://mirrors.cnssuestc.org/archlinuxcn/$arch
, or ask @KaseiWang or @pandada8 to add https support to this mirror.