今天安装了一个新的测试环境，在安装相关插件之前对Ubuntu进行系统更新，试用的命令有：

sudo apt update
sudo apt upgrade

但两个命令都出现错误：SECURITY: URL redirect target contains control characters, rejecting,详细的日志如下：

注意到日志的内容，多次出现rejecting. [IP:14.29.39.222 80], 问了下公司网管说并没有对这个ip进行限制，不过对一些80和8080的网络端口进行限制。

查了下网上的信息，发现也有网友遇到类似的问题，问题的原因都指向：某信服的上网管理软件。

既然不让访问80端口，那么我们只能把更新源换成443端口，也就是强制改变网络请求的协议。步骤如下：

通过命令sudo vim /etc/apt/sources.list将所有的http改成https即可。

更改后，内容如下所示：

# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb https://mirrors.aliyun.com/ubuntu bionic main restricted
# deb-src http://mirrors.aliyun.com/ubuntu bionic main restricted

## Major bug fix updates produced after the final release of the
## distribution.
deb https://mirrors.aliyun.com/ubuntu bionic-updates main restricted
# deb-src http://mirrors.aliyun.com/ubuntu bionic-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 https://mirrors.aliyun.com/ubuntu bionic universe
# deb-src http://mirrors.aliyun.com/ubuntu bionic universe
deb https://mirrors.aliyun.com/ubuntu bionic-updates universe
# deb-src http://mirrors.aliyun.com/ubuntu bionic-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 https://mirrors.aliyun.com/ubuntu bionic multiverse
# deb-src http://mirrors.aliyun.com/ubuntu bionic multiverse
deb https://mirrors.aliyun.com/ubuntu bionic-updates multiverse
# deb-src http://mirrors.aliyun.com/ubuntu bionic-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 https://mirrors.aliyun.com/ubuntu bionic-backports main restricted universe multiverse
# deb-src http://mirrors.aliyun.com/ubuntu bionic-backports main restricted universe 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 bionic partner
# deb-src http://archive.canonical.com/ubuntu bionic partner

deb https://mirrors.aliyun.com/ubuntu bionic-security main restricted
# deb-src http://mirrors.aliyun.com/ubuntu bionic-security main restricted
deb https://mirrors.aliyun.com/ubuntu bionic-security universe
# deb-src http://mirrors.aliyun.com/ubuntu bionic-security universe
deb https://mirrors.aliyun.com/ubuntu bionic-security multiverse
deb [arch=amd64] https://download.docker.com/linux/ubuntu bionic stable
# deb-src [arch=amd64] https://download.docker.com/linux/ubuntu bionic stable
# deb-src http://mirrors.aliyun.com/ubuntu bionic-security multiverse

经过测试，可以通过某信服的网络限制，顺利拉到更新。