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安装snapd

添加EPEL

简单理解EPEL是一个软件库的扩展，官方软件源有限，安装snapd一定要先添加EPEL。

sudo dnf install epel-release
sudo dnf upgrade # 这一步将比较耗时

通过yum安装snapd

通过snap安装certbot

通过certbot安装证书

Running transaction
RPM: warning: Found bdb_ro Packages database while attempting sqlite backend: using bdb_ro backend.
RPM: error: cannot open Packages index using bdb_ro - Operation not permitted (1)
RPM: error: cannot open Packages database in /var/lib/rpm
The downloaded packages were saved in cache until the next successful transaction.
You can remove cached packages by executing 'dnf clean packages'.
Error: Could not run transaction.

解决方案：

sudo rpm --rebuilddb # 重建RPM数据库
sudo dnf clean all

https://www.cnblogs.com/aymar/p/14484225.html
https://junyao.tech/posts/51c3229.html