我有一个 Debian Squeeze EC2 AMI。在用它启动实例并尝试使用 apt-get 安装软件包时，我收到错误消息，提示未安装密钥环。以下是使用 apt-get update 时出现的错误：
root@ip:~# apt-get update
Get:1 http://ftp.us.debian.org squeeze Release.gpg [1672 B]
Ign http://ftp.us.debian.org/debian/ squeeze/contrib Translation-en
Ign http://ftp.us.debian.org/debian/ squeeze/main Translation-en
Ign http://ftp.us.debian.org/debian/ squeeze/non-free Translation-en
Get:2 http://security.debian.org squeeze/updates Release.gpg [836 B]
Ign http://security.debian.org/ squeeze/updates/contrib Translation-en
Ign http://security.debian.org/ squeeze/updates/main Translation-en
Hit http://ftp.us.debian.org squeeze Release
Ign http://ftp.us.debian.org squeeze Release
Ign http://security.debian.org/ squeeze/updates/non-free Translation-en
Ign http://ftp.us.debian.org squeeze/main Sources/DiffIndex
Get:3 http://security.debian.org squeeze/updates Release [86.9 kB]
Ign http://security.debian.org squeeze/updates Release
Ign http://ftp.us.debian.org squeeze/contrib Sources/DiffIndex
Ign http://ftp.us.debian.org squeeze/non-free Sources/DiffIndex
Ign http://ftp.us.debian.org squeeze/main amd64 Packages/DiffIndex
Ign http://ftp.us.debian.org squeeze/contrib amd64 Packages/DiffIndex
Ign http://ftp.us.debian.org squeeze/non-free amd64 Packages/DiffIndex
Ign http://security.debian.org squeeze/updates/main Sources/DiffIndex
Hit http://ftp.us.debian.org squeeze/main Sources
Hit http://ftp.us.debian.org squeeze/contrib Sources
Hit http://ftp.us.debian.org squeeze/non-free Sources
Hit http://ftp.us.debian.org squeeze/main amd64 Packages
Hit http://ftp.us.debian.org squeeze/contrib amd64 Packages
Ign http://security.debian.org squeeze/updates/contrib Sources/DiffIndex
Ign http://security.debian.org squeeze/updates/non-free Sources/DiffIndex
Ign http://security.debian.org squeeze/updates/main amd64 Packages/DiffIndex
Ign http://security.debian.org squeeze/updates/contrib amd64 Packages/DiffIndex
Ign http://security.debian.org squeeze/updates/non-free amd64 Packages/DiffIndex
Hit http://ftp.us.debian.org squeeze/non-free amd64 Packages
Get:4 http://backports.debian.org squeeze-backports Release.gpg [836 B]
Ign http://backports.debian.org/debian-backports/ squeeze-backports/main Translation-en
Hit http://security.debian.org squeeze/updates/main Sources
Hit http://security.debian.org squeeze/updates/contrib Sources
Hit http://security.debian.org squeeze/updates/non-free Sources
Hit http://security.debian.org squeeze/updates/main amd64 Packages
Hit http://security.debian.org squeeze/updates/contrib amd64 Packages
Hit http://security.debian.org squeeze/updates/non-free amd64 Packages
Get:5 http://backports.debian.org squeeze-backports Release [77.6 kB]
Ign http://backports.debian.org squeeze-backports Release
Hit http://backports.debian.org squeeze-backports/main amd64 Packages/DiffIndex
Hit http://backports.debian.org squeeze-backports/main amd64 Packages
Fetched 3346 B in 0s (5298 B/s)
Reading package lists... Done
W: GPG error: http://ftp.us.debian.org squeeze Release: No keyring installed in /etc/apt/trusted.gpg.d/.
W: GPG error: http://security.debian.org squeeze/updates Release: No keyring installed in /etc/apt/trusted.gpg.d/.
W: GPG error: http://backports.debian.org squeeze-backports Release: No keyring installed in /etc/apt/trusted.gpg.d/.
谷歌搜索并没有真正帮助我解决这个问题。我尝试安装软件包“debian-keyring”和“debian-archive-keyring”，但错误并没有消失。我想避免安装不受信任的软件包。任何帮助都非常感谢！为什么会发生此错误？我在哪里可以了解更多信息？
答案1
最后修复了这个问题：
wget --no-check-certificate https://ftp-master.debian.org/keys/archive-key-6.0.asc
&& apt-key add archive-key-6.0.asc
apt-get update
apt-get install --reinstall debian-keyring debian-archive-keyring
apt-get update