我想为我的域获取 Letsencrpyt SSL。该过程的一部分是，该站点需要在获得证书之前获得授权。
我创建了文件夹./well-known并运行了我被要求执行的命令，我得到了；
Nginx 403 forbidden.
我在 nginx/1.10.0 (Ubuntu)
我chown的目录并授予它755但仍然相同。查看下面我的目录中的权限。
namei -l /var/www/example.com/.well-known
f: /var/www/example.com/.well-known
drwxr-xr-x root root /
drwxr-xr-x root root var
drwxr-xr-x root root www
drwxr-xr-x cman sudo example.com
drwxr-xr-x cman sudo .well-known
我还在working.html文件/.well-known夹中创建了一个文件并加载example.com/.well-known/working.html，我得到了相同的 403 Forbidden。
配置文件
upstream kip_app_server {
# fail_timeout=0 means we always retry an upstream even if it failed
# to return a good HTTP response (in case the Gunicorn master nukes …操作系统：Ubuntu 16.04
我想在Digitalocean的512mb RAM VPS服务器上安装redis-server，我重新执行命令，我得到了，
Extracting templates from packages: 100%
Preconfiguring packages ...
(Reading database ... 311316 files and directories currently installed.)
Preparing to unpack .../libisc-export160_1%3a9.10.3.dfsg.P4-
8ubuntu1.9_amd64.deb ...
Unpacking libisc-export160 (1:9.10.3.dfsg.P4-8ubuntu1.9) over
(1:9.10.3.dfsg.P4-8ubuntu1.7) ...
dpkg: unrecoverable fatal error, aborting:
fork failed: Cannot allocate memory
E: Sub-process /usr/bin/dpkg returned an error code (2)
我跑了sudo dpkg --configure -a和sudo apt-get -f install，我得到了
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following additional packages will be installed:
libisc-export160
The following …