我正在关注 iRedmail 文档，看到了这一行
iRedMail 需要官方 Debian/Ubuntu apt 存储库，请在 中启用它们/etc/apt/sources.list。
我该如何检查这是否属实？
我使用的是 16.04 无头服务器版本
答案1
使用 16.04 Ubuntu headless 进行测试
cat /etc/apt/sources.list
你应该看到类似
## Note, this file is written by cloud-init on first boot of an instance
## modifications made here will not survive a re-bundle.
## if you wish to make changes you can:
## a.) add 'apt_preserve_sources_list: true' to /etc/cloud/cloud.cfg
## or do the same in user-data
## b.) add sources in /etc/apt/sources.list.d
## c.) make changes to template file /etc/cloud/templates/sources.list.tmpl
# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb http://ap-southeast-1.ec2.archive.ubuntu.com/ubuntu/ xenial main restricted
deb-src http://ap-southeast-1.ec2.archive.ubuntu.com/ubuntu/ xenial main restricted
## Major bug fix updates produced after the final release of the
## distribution.
deb http://ap-southeast-1.ec2.archive.ubuntu.com/ubuntu/ xenial-updates main restricted
deb-src http://ap-southeast-1.ec2.archive.ubuntu.com/ubuntu/ xenial-updates main restricted
## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team. Also, please note that software in universe WILL NOT receive any
## review or updates from the Ubuntu security team.
deb http://ap-southeast-1.ec2.archive.ubuntu.com/ubuntu/ xenial universe
deb-src http://ap-southeast-1.ec2.archive.ubuntu.com/ubuntu/ xenial universe
deb http://ap-southeast-1.ec2.archive.ubuntu.com/ubuntu/ xenial-updates universe
deb-src http://ap-southeast-1.ec2.archive.ubuntu.com/ubuntu/ xenial-updates universe
## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team, and may not be under a free licence. Please satisfy yourself as to
## your rights to use the software. Also, please note that software in
## multiverse WILL NOT receive any review or updates from the Ubuntu
## security team.
deb http://ap-southeast-1.ec2.archive.ubuntu.com/ubuntu/ xenial multiverse
deb-src http://ap-southeast-1.ec2.archive.ubuntu.com/ubuntu/ xenial multiverse
deb http://ap-southeast-1.ec2.archive.ubuntu.com/ubuntu/ xenial-updates multiverse
deb-src http://ap-southeast-1.ec2.archive.ubuntu.com/ubuntu/ xenial-updates multiverse
## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
deb http://ap-southeast-1.ec2.archive.ubuntu.com/ubuntu/ xenial-backports main restricted universe multiverse
deb-src http://ap-southeast-1.ec2.archive.ubuntu.com/ubuntu/ xenial-backports main restricted universe multiverse
deb http://security.ubuntu.com/ubuntu xenial-security main restricted
deb-src http://security.ubuntu.com/ubuntu xenial-security main restricted
deb http://security.ubuntu.com/ubuntu xenial-security universe
deb-src http://security.ubuntu.com/ubuntu xenial-security universe
deb http://security.ubuntu.com/ubuntu xenial-security multiverse
deb-src http://security.ubuntu.com/ubuntu xenial-security multiverse
## Uncomment the following two lines to add software from Canonical's
## 'partner' repository.
## This software is not part of Ubuntu, but is offered by Canonical and the
## respective vendors as a service to Ubuntu users.
# deb http://archive.canonical.com/ubuntu xenial partner
# deb-src http://archive.canonical.com/ubuntu xenial partner
通常带有描述的存储库main是官方支持的存储库。