我是 juju 魅力的新手，我正在尝试按照youtube 教程安装 juju 魅力工具。
我已经在 Windows 盒子上安装了 ubuntu 的 vm 映像。ubuntu 版本详情如下：
Linux vagrant-ubuntu-vivid-64 3.19.0-21-generic #21-Ubuntu SMP Sun Jun 14 18:31:11 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux
我能够成功运行教程中提到的步骤，直到“juju bootstrap”。仅对于 juju bootstrap，我收到以下错误 -
Bootstrapping environment "local"
Starting new instance for initial state server
Building tools to upload (1.24.3.1-vivid-amd64)
Bootstrapping environment "local"
Starting new instance for initial state server
Building tools to upload (1.24.3.1-vivid-amd64)
Installing Juju agent on bootstrap instance
Logging to /home/vagrant/.juju/local/cloud-init-output.log on remote host
Installing package: curl
Installing package: cpu-checker
Installing package: bridge-utils
Installing package: rsyslog-gnutls
Installing package: cloud-utils
Installing package: cloud-image-utils
Installing package: tmux
Bootstrapping Juju machine agent
Reading package lists...
Building dependency tree...
Reading state information...
curl is already the newest version.
0 upgraded, 0 newly installed, 0 to remove and 24 not upgraded.
Reading package lists...
Building dependency tree...
Reading state information...
cpu-checker is already the newest version.
cpu-checker set to manually installed.
0 upgraded, 0 newly installed, 0 to remove and 24 not upgraded.
Reading package lists...
Building dependency tree...
Reading state information...
bridge-utils is already the newest version.
bridge-utils set to manually installed.
0 upgraded, 0 newly installed, 0 to remove and 24 not upgraded.
Reading package lists...
Building dependency tree...
Reading state information...
rsyslog-gnutls is already the newest version.
rsyslog-gnutls set to manually installed.
0 upgraded, 0 newly installed, 0 to remove and 24 not upgraded.
Reading package lists...
Building dependency tree...
Reading state information...
The following NEW packages will be installed:
cloud-utils
0 upgraded, 1 newly installed, 0 to remove and 24 not upgraded.
Need to get 1,568 B of archives.
After this operation, 31.7 kB of additional disk space will be used.
Get:1 http://archive.ubuntu.com/ubuntu/ vivid/main cloud-utils all 0.27-0ubuntu15 [1,568 B]
Fetched 1,568 B in 5s (296 B/s)
Selecting previously unselected package cloud-utils.
(Reading database ... 66876 files and directories currently installed.)
Preparing to unpack .../cloud-utils_0.27-0ubuntu15_all.deb ...
Unpacking cloud-utils (0.27-0ubuntu15) ...
Setting up cloud-utils (0.27-0ubuntu15) ...
Reading package lists...
Building dependency tree...
Reading state information...
cloud-image-utils is already the newest version.
cloud-image-utils set to manually installed.
0 upgraded, 0 newly installed, 0 to remove and 24 not upgraded.
Reading package lists...
Building dependency tree...
Reading state information...
tmux is already the newest version.
0 upgraded, 0 newly installed, 0 to remove and 24 not upgraded.
945f7daba6d7d7f7d441d6536d513a61b6ccaf92d858bbc86a0038c9b97bd01d /home/vagrant/.juju/local/tools/1.24.3.1-vivid-amd64/tools.tar.gz
2015-07-29 21:37:51 INFO juju.cmd supercommand.go:37 running jujud [1.24.3.1-vivid-amd64 gc]
2015-07-29 21:37:51 INFO juju.network network.go:194 setting prefer-ipv6 to false
2015-07-29 21:37:51 INFO juju.provider.local environprovider.go:38 opening environment "local"
2015-07-29 21:37:54 INFO juju.agent identity.go:22 writing system identity file
2015-07-29 21:37:54 INFO juju.mongo mongo.go:173 Ensuring mongo server is running; data directory /home/vagrant/.juju/local; port 37017
2015-07-29 21:37:54 INFO juju.mongo mongo.go:348 installing juju-mongodb
2015-07-29 21:37:54 INFO juju.utils.packaging.manager utils.go:57 Running: apt-get --option=Dpkg::Options::=--force-confold --option=Dpkg::options::=--force-unsafe-io --assume-yes --quiet install juju-mongodb
2015-07-29 21:42:55 INFO juju.worker.peergrouper initiate.go:77 finished MaybeInitiateMongoServer
***> **2015-07-29 21:42:55 错误 juju.cmd supercommand.go:430 无法启动副本集：无法拨打 mongo 来启动副本集：否
可访问的服务器错误无法引导环境：退出状态 1*****
我已经尝试过破坏环境并再次运行引导命令。从消息看来，juju-mongodb 已安装，但我没有看到该服务正在运行。我无法使用 - 运行服务
sudo 服务 mongodb 启动。
输出是：
vagrant@vagrant-ubuntu-vivid-64:~$ sudo service mongod start 启动 mongod.service 失败：单元 mongod.service 加载失败：没有这样的文件或目录。
我究竟做错了什么？如何检查 mongodb 是否安装正确？