我正在尝试将 wheezy 更新为 jessie 并出现重复的源错误
apt-get update
...
Reading package lists... Done
W: Duplicate sources.list entry http://ftp.uk.debian.org/debian/ jessie/main i386 Packages (/var/lib/apt/lists/ftp.uk.debian.org_debian_dists_jessie_main_binary-i386_Packages)
W: You may want to run apt-get update to correct these problems
其内容/etc/apt/sources.list为：
deb http://ftp.uk.debian.org/debian/ jessie main
#deb-src http://ftp.uk.debian.org/debian/ jessie main
deb http://security.debian.org/ jessie/updates main
#deb-src http://security.debian.org/ jessie/updates main
# jessie-updates, previously known as 'volatile'
deb http://ftp.uk.debian.org/debian/ jessie-updates main
#deb-src http://ftp.uk.debian.org/debian/ jessie-updates main
deb http://ftp.uk.debian.org/debian/ jessie main contrib non-free
#deb-src http://ftp.uk.debian.org/debian/ jessie main contrib non-free
的内容/var/lib/apt/lists/是
ftp.uk.debian.org_debian_dists_jessie_contrib_binary-i386_Packages
ftp.uk.debian.org_debian_dists_jessie_contrib_i18n_Translation-en
ftp.uk.debian.org_debian_dists_jessie_main_binary-i386_Packages
ftp.uk.debian.org_debian_dists_jessie_main_i18n_Translation-en
ftp.uk.debian.org_debian_dists_jessie_non-free_binary-i386_Packages
ftp.uk.debian.org_debian_dists_jessie_non-free_i18n_Translation-en
ftp.uk.debian.org_debian_dists_jessie_Release
ftp.uk.debian.org_debian_dists_jessie_Release.gpg
ftp.uk.debian.org_debian_dists_jessie-updates_main_binary-i386_Packages
ftp.uk.debian.org_debian_dists_jessie-updates_main_binary-i386_Packages.IndexDiff
ftp.uk.debian.org_debian_dists_jessie-updates_main_i18n_Translation-en
ftp.uk.debian.org_debian_dists_jessie-updates_main_i18n_Translation-en.IndexDiff
ftp.uk.debian.org_debian_dists_jessie-updates_Release
ftp.uk.debian.org_debian_dists_jessie-updates_Release.gpg
lock
partial
security.debian.org_dists_jessie_updates_main_binary-i386_Packages
security.debian.org_dists_jessie_updates_main_i18n_Translation-en
security.debian.org_dists_jessie_updates_Release
security.debian.org_dists_jessie_updates_Release.gpg
请帮忙，我是新手，不知道我哪里出错了。
答案1
线路
deb http://ftp.uk.debian.org/debian/ jessie main contrib non-free
在你的/etc/apt/sources.list是重复/扩展
deb http://ftp.uk.debian.org/debian/ jessie main
删除较短的行。
至少在理论上，/etc/apt/sources.list.d/*文件中的行也可能存在更多重复。