curl: (35) SSL connect error 提示升级nss。但是升级报错，因为升级需要https，并且服务器是centos6，已经被禁止镜像源 一下配置只针对centos6 CentOS-Base.repo ``` [base] name=CentOS-$releasever failovermethod=priority baseurl=http://vault.centos.org/6.10/os/x86_64/ gpgcheck=1 gpgkey=http://vault.centos.org/6.10/os/x86_64/RPM-GPG-KEY-CentOS-6 [updates] name=CentOS-$releasever enabled=1 failovermethod=priority baseurl=http://vault.centos.org/6.10/updates/$basearch/ gpgcheck=1 gpgkey=http://vault.centos.org/6.10/os/x86_64/RPM-GPG-KEY-CentOS-6 [extras] name=CentOS-$releasever enabled=1 failovermethod=priority baseurl=http://vault.centos.org/6.10/extras/$basearch/ gpgcheck=1 gpgkey=http://vault.centos.org/6.10/os/x86_64/RPM-GPG-KEY-CentOS-6 ``` epel.repo ``` [epel] name=Extra Packages for Enterprise Linux 6 - $basearch baseurl=http://download.fedoraproject.org/pub/epel/6/$basearch #mirrorlist=http://mirrors.fedoraproject.org/metalink?repo=epel-6&arch=$basearch failovermethod=priority enabled=0 gpgcheck=1 gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL-6 ``` 查找yum.repos.d下面所有文件包含https的，全部换成http