查看无线网卡：

/sbin/lspci | grep Broadcom

或

lspci | grep Network

确定是Broadcom BCM43142

安装fusion rpm源

yum install https://download1.rpmfusion.org/free/el/rpmfusion-free-release-8.noarch.rpm

yum install https://download1.rpmfusion.org/nonfree/el/rpmfusion-nonfree-release-8.noarch.rpm

安装

dnf install kernel-devel

dnf install broadcom-wl akmod-wl akmods

akmods
dnf update

重启系统后，无线网卡可见了。