我知道有几十个“apt-get update：获取失败”的问题（我读了所有能找到的问题），但我目前的情况是 12.04 独有的，它影响所有来源；不仅仅是 launchpad。此外，我尝试了欧洲和美国的几个不同的服务器以及“主服务器”（无论它在哪里），它们都产生了相同的结果：我无法连接到任何软件源。
此外，我相当确定问题源于我今天早上执行的从 11.10->12.04 的升级，因为更新在此之前立即生效。
来自更新管理器的更新工作正常，我可以毫无意外地从软件中心下载一些东西（咕哝），这让我认为我可以连接到 Ubuntu 服务器的某些子集（但是，其他几个 Ubuntu 服务器 - 如附加服务器 - 和一些规范服务器被列为“无法连接”）。
以下是 的输出sudo apt-get update：
sudo apt-get update
Ign http://ftp.u-picardie.fr precise InRelease
Ign http://archive.canonical.com precise InRelease
Ign http://ftp.u-picardie.fr precise-updates InRelease
Ign http://ftp.u-picardie.fr precise-backports InRelease
Err http://ftp.u-picardie.fr precise-security InRelease
Err http://ftp.u-picardie.fr precise Release.gpg
Unable to connect to ftp.u-picardie.fr:http:
Err http://ftp.u-picardie.fr precise-updates Release.gpg
Unable to connect to ftp.u-picardie.fr:http:
Err http://ftp.u-picardie.fr precise-backports Release.gpg
Unable to connect to ftp.u-picardie.fr:http:
Err http://ftp.u-picardie.fr precise-security Release.gpg
Unable to connect to ftp.u-picardie.fr:http:
Hit http://archive.canonical.com precise Release.gpg
Hit http://archive.canonical.com precise Release
Hit http://archive.canonical.com precise/partner i386 Packages
Ign http://archive.canonical.com precise/partner TranslationIndex
Ign http://dl.google.com stable InRelease
Ign http://dl.google.com stable InRelease
Err http://archive.canonical.com precise/partner Translation-en_US
Unable to connect to archive.canonical.com:http: [IP: 91.189.92.150 80]
Err http://archive.canonical.com precise/partner Translation-en
Unable to connect to archive.canonical.com:http: [IP: 91.189.92.150 80]
Ign http://extras.ubuntu.com precise InRelease
Get:1 http://dl.google.com stable Release.gpg [198 B]
Err http://extras.ubuntu.com precise Release.gpg
Could not connect to extras.ubuntu.com:80 (91.189.88.33). - connect (111: Connection refused)
Ign http://ppa.launchpad.net precise InRelease
Err http://ppa.launchpad.net precise InRelease
Err http://ppa.launchpad.net precise InRelease
Err http://ppa.launchpad.net precise InRelease
Err http://ppa.launchpad.net precise InRelease
Err http://ppa.launchpad.net precise InRelease
Err http://ppa.launchpad.net precise InRelease
Err http://ppa.launchpad.net precise InRelease
Err http://ppa.launchpad.net precise InRelease
Get:2 http://dl.google.com stable Release.gpg [198 B]
Err http://ppa.launchpad.net precise Release.gpg
Unable to connect to ppa.launchpad.net:http:
Err http://ppa.launchpad.net precise Release.gpg
Unable to connect to ppa.launchpad.net:http:
Err http://ppa.launchpad.net precise Release.gpg
Unable to connect to ppa.launchpad.net:http:
Err http://ppa.launchpad.net precise Release.gpg
Unable to connect to ppa.launchpad.net:http:
Err http://ppa.launchpad.net precise Release.gpg
Unable to connect to ppa.launchpad.net:http:
Err http://ppa.launchpad.net precise Release.gpg
Unable to connect to ppa.launchpad.net:http:
Err http://ppa.launchpad.net precise Release.gpg
Unable to connect to ppa.launchpad.net:http:
Err http://ppa.launchpad.net precise Release.gpg
Unable to connect to ppa.launchpad.net:http:
Err http://ppa.launchpad.net precise Release.gpg
Unable to connect to ppa.launchpad.net:http:
Get:3 http://dl.google.com stable Release [1,347 B]
Get:4 http://dl.google.com stable Release [1,347 B]
Get:5 http://dl.google.com stable/main i386 Packages [1,268 B]
Ign http://dl.google.com stable/main TranslationIndex
Get:6 http://dl.google.com stable/main i386 Packages [769 B]
Ign http://dl.google.com stable/main TranslationIndex
Ign http://dl.google.com stable/main Translation-en_US
Ign http://dl.google.com stable/main Translation-en
Ign http://dl.google.com stable/main Translation-en_US
Ign http://dl.google.com stable/main Translation-en
Fetched 5,127 B in 7s (673 B/s)
Reading package lists... Done
W: Failed to fetch http://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/dists/precise-security/InRelease
W: Failed to fetch http://ppa.launchpad.net/elementary-os/stable/ubuntu/dists/precise/InRelease
W: Failed to fetch http://ppa.launchpad.net/elementaryart/elementary-dev/ubuntu/dists/precise/InRelease
W: Failed to fetch http://ppa.launchpad.net/midori/ppa/ubuntu/dists/precise/InRelease
W: Failed to fetch http://ppa.launchpad.net/nemequ/sqlheavy/ubuntu/dists/precise/InRelease
W: Failed to fetch http://ppa.launchpad.net/ricotz/docky/ubuntu/dists/precise/InRelease
W: Failed to fetch http://ppa.launchpad.net/sgringwe/beatbox/ubuntu/dists/precise/InRelease
W: Failed to fetch http://ppa.launchpad.net/webupd8team/y-ppa-manager/ubuntu/dists/precise/InRelease
W: Failed to fetch http://ppa.launchpad.net/yorba/ppa/ubuntu/dists/precise/InRelease
W: Failed to fetch http://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/dists/precise/Release.gpg Unable to connect to ftp.u-picardie.fr:http:
W: Failed to fetch http://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/dists/precise-updates/Release.gpg Unable to connect to ftp.u-picardie.fr:http:
W: Failed to fetch http://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/dists/precise-backports/Release.gpg Unable to connect to ftp.u-picardie.fr:http:
W: Failed to fetch http://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/dists/precise-security/Release.gpg Unable to connect to ftp.u-picardie.fr:http:
W: Failed to fetch http://archive.canonical.com/ubuntu/dists/precise/partner/i18n/Translation-en_US Unable to connect to archive.canonical.com:http: [IP: 91.189.92.150 80]
W: Failed to fetch http://archive.canonical.com/ubuntu/dists/precise/partner/i18n/Translation-en Unable to connect to archive.canonical.com:http: [IP: 91.189.92.150 80]
W: Failed to fetch http://extras.ubuntu.com/ubuntu/dists/precise/Release.gpg Could not connect to extras.ubuntu.com:80 (91.189.88.33). - connect (111: Connection refused)
W: Failed to fetch http://ppa.launchpad.net/caffeine-developers/ppa/ubuntu/dists/precise/Release.gpg Unable to connect to ppa.launchpad.net:http:
W: Failed to fetch http://ppa.launchpad.net/elementary-os/stable/ubuntu/dists/precise/Release.gpg Unable to connect to ppa.launchpad.net:http:
W: Failed to fetch http://ppa.launchpad.net/elementaryart/elementary-dev/ubuntu/dists/precise/Release.gpg Unable to connect to ppa.launchpad.net:http:
W: Failed to fetch http://ppa.launchpad.net/midori/ppa/ubuntu/dists/precise/Release.gpg Unable to connect to ppa.launchpad.net:http:
W: Failed to fetch http://ppa.launchpad.net/nemequ/sqlheavy/ubuntu/dists/precise/Release.gpg Unable to connect to ppa.launchpad.net:http:
W: Failed to fetch http://ppa.launchpad.net/ricotz/docky/ubuntu/dists/precise/Release.gpg Unable to connect to ppa.launchpad.net:http:
W: Failed to fetch http://ppa.launchpad.net/sgringwe/beatbox/ubuntu/dists/precise/Release.gpg Unable to connect to ppa.launchpad.net:http:
W: Failed to fetch http://ppa.launchpad.net/webupd8team/y-ppa-manager/ubuntu/dists/precise/Release.gpg Unable to connect to ppa.launchpad.net:http:
W: Failed to fetch http://ppa.launchpad.net/yorba/ppa/ubuntu/dists/precise/Release.gpg Unable to connect to ppa.launchpad.net:http:
W: Some index files failed to download. They have been ignored, or old ones used instead.
W: Duplicate sources.list entry http://ppa.launchpad.net/nemequ/sqlheavy/ubuntu/ precise/main i386 Packages (/var/lib/apt/lists/ppa.launchpad.net_nemequ_sqlheavy_ubuntu_dists_precise_main_binary-i386_Packages)
W: Duplicate sources.list entry http://ppa.launchpad.net/sgringwe/beatbox/ubuntu/ precise/main i386 Packages (/var/lib/apt/lists/ppa.launchpad.net_sgringwe_beatbox_ubuntu_dists_precise_main_binary-i386_Packages)
内容/etc/apt/sources.list：
# deb cdrom:[Ubuntu 11.10 _Oneiric Ocelot_ - Release i386 (20111012)]/ oneiric main restricted
deb-src http://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/ precise main restricted #Added by software-properties
# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb http://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/ precise main restricted
deb-src http://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/ precise multiverse universe #Added by software-properties
## Major bug fix updates produced after the final release of the
## distribution.
deb http://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/ precise-updates main restricted
deb-src http://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/ precise-updates restricted main multiverse universe #Added by software-properties
## 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://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/ precise universe
deb http://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/ precise-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://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/ precise multiverse
deb http://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/ precise-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://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/ precise-backports main restricted universe multiverse
deb-src http://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/ precise-backports main restricted universe multiverse #Added by software-properties
deb http://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/ precise-security main restricted
deb-src http://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/ precise-security restricted main multiverse universe #Added by software-properties
deb http://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/ precise-security universe
deb http://ftp.u-picardie.fr/mirror/ubuntu/ubuntu/ precise-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 oneiric partner
# deb-src http://archive.canonical.com/ubuntu oneiric partner
## This software is not part of Ubuntu, but is offered by third-party
## developers who want to ship their latest software.
deb http://extras.ubuntu.com/ubuntu precise main
deb-src http://extras.ubuntu.com/ubuntu precise main
测试替代sources.list文件
这些是我遵循的步骤来产生以下输出：
请备份您的 sources.list：
sudo cp /etc/apt/sources.list /etc/apt/sources.list.backup/etc/apt/sources.list然后用以下几行替换的内容并运行apt-get update：
deb http://archive.ubuntu.com/ubuntu/ 精确 主要 受限 宇宙 多元宇宙 deb http://archive.ubuntu.com/ubuntu/ precise-updates 主要受限宇宙多元宇宙 deb http://archive.ubuntu.com/ubuntu/ precise-backports 主要受限宇宙多元宇宙 deb http://security.ubuntu.com/ubuntu precise-security 主要受限宇宙多元宇宙 deb http://archive.canonical.com/ubuntu 精准合作伙伴 deb http://extras.ubuntu.com/ubuntu 精确的主要
输出：
someone@someone-UBook:~$ sudo apt-get update
Ign http://archive.canonical.com precise InRelease
Hit http://archive.canonical.com precise Release.gpg
Hit http://archive.canonical.com precise Release
Ign http://archive.ubuntu.com precise InRelease
Ign http://extras.ubuntu.com precise InRelease
Ign http://archive.ubuntu.com precise-updates InRelease
Hit http://archive.canonical.com precise/partner i386 Packages
Hit http://extras.ubuntu.com precise Release.gpg
Ign http://archive.ubuntu.com precise-backports InRelease
Ign http://archive.canonical.com precise/partner TranslationIndex
Err http://archive.canonical.com precise/partner Translation-en_US
Unable to connect to archive.canonical.com:http: [IP: 91.189.92.150 80]
Err http://archive.canonical.com precise/partner Translation-en
Unable to connect to archive.canonical.com:http: [IP: 91.189.92.150 80]
Hit http://extras.ubuntu.com precise Release
Get:1 http://archive.ubuntu.com precise Release.gpg [198 B]
Ign http://dl.google.com stable InRelease
Err http://dl.google.com stable InRelease
Err http://dl.google.com stable Release.gpg
Unable to connect to dl.google.com:http: [IP: 173.194.34.38 80]
Err http://dl.google.com stable Release.gpg
Unable to connect to dl.google.com:http: [IP: 173.194.34.38 80]
Get:2 http://archive.ubuntu.com precise-updates Release.gpg [198 B]
Hit http://extras.ubuntu.com precise/main i386 Packages
Get:3 http://archive.ubuntu.com precise-backports Release.gpg [198 B]
Ign http://security.ubuntu.com precise-security InRelease
Ign http://extras.ubuntu.com precise/main TranslationIndex
Err http://extras.ubuntu.com precise/main Translation-en_US
Unable to connect to extras.ubuntu.com:http:
Err http://extras.ubuntu.com precise/main Translation-en
Unable to connect to extras.ubuntu.com:http:
Get:4 http://security.ubuntu.com precise-security Release.gpg [198 B]
Get:5 http://archive.ubuntu.com precise Release [49.6 kB]
Get:6 http://security.ubuntu.com precise-security Release [49.6 kB]
Get:7 http://archive.ubuntu.com precise-updates Release [49.6 kB]
Get:8 http://archive.ubuntu.com precise-backports Release [49.6 kB]
Get:9 http://security.ubuntu.com precise-security/main i386 Packages [32.9 kB]
Get:10 http://archive.ubuntu.com precise/main i386 Packages [1,274 kB]
Get:11 http://security.ubuntu.com precise-security/restricted i386 Packages [14 B]
Get:12 http://security.ubuntu.com precise-security/universe i386 Packages [8,594 B]
Get:13 http://security.ubuntu.com precise-security/multiverse i386 Packages [1,393 B]
Get:14 http://security.ubuntu.com precise-security/main TranslationIndex [73 B]
Get:15 http://security.ubuntu.com precise-security/multiverse TranslationIndex [71 B]
Get:16 http://security.ubuntu.com precise-security/restricted TranslationIndex [70 B]
Get:17 http://security.ubuntu.com precise-security/universe TranslationIndex [72 B]
Get:18 http://security.ubuntu.com precise-security/main Translation-en [13.6 kB]
Get:19 http://security.ubuntu.com precise-security/multiverse Translation-en [587 B]
Get:20 http://security.ubuntu.com precise-security/restricted Translation-en [14 B]
Get:21 http://security.ubuntu.com precise-security/universe Translation-en [6,261 B]
Get:22 http://archive.ubuntu.com precise/restricted i386 Packages [8,431 B]
Get:23 http://archive.ubuntu.com precise/universe i386 Packages [4,796 kB]
Ign http://ppa.launchpad.net precise InRelease
Ign http://ppa.launchpad.net precise InRelease
Ign http://ppa.launchpad.net precise InRelease
Ign http://ppa.launchpad.net precise InRelease
Ign http://ppa.launchpad.net precise InRelease
Ign http://ppa.launchpad.net precise InRelease
Ign http://ppa.launchpad.net precise InRelease
Ign http://ppa.launchpad.net precise InRelease
Ign http://ppa.launchpad.net precise InRelease
Ign http://ppa.launchpad.net precise InRelease
Ign http://ppa.launchpad.net precise InRelease
Get:24 http://ppa.launchpad.net precise Release.gpg [316 B]
Get:25 http://ppa.launchpad.net precise Release.gpg [316 B]
Get:26 http://ppa.launchpad.net precise Release.gpg [316 B]
Ign http://ppa.launchpad.net precise Release.gpg
Get:27 http://ppa.launchpad.net precise Release.gpg [316 B]
Hit http://ppa.launchpad.net precise Release.gpg
Get:28 http://ppa.launchpad.net precise Release.gpg [316 B]
Get:29 http://ppa.launchpad.net precise Release.gpg [316 B]
Hit http://ppa.launchpad.net precise Release.gpg
Get:30 http://ppa.launchpad.net precise Release.gpg [316 B]
Hit http://ppa.launchpad.net precise Release.gpg
Get:31 http://ppa.launchpad.net precise Release [11.9 kB]
Get:32 http://ppa.launchpad.net precise Release [11.9 kB]
Get:33 http://archive.ubuntu.com precise/multiverse i386 Packages [121 kB]
Get:34 http://ppa.launchpad.net precise Release [11.9 kB]
Ign http://ppa.launchpad.net precise Release
Get:35 http://ppa.launchpad.net precise Release [11.9 kB]
Hit http://archive.ubuntu.com precise/main TranslationIndex
Hit http://archive.ubuntu.com precise/multiverse TranslationIndex
Hit http://ppa.launchpad.net precise Release
Hit http://archive.ubuntu.com precise/restricted TranslationIndex
Get:36 http://ppa.launchpad.net precise Release [11.9 kB]
Hit http://archive.ubuntu.com precise/universe TranslationIndex
Get:37 http://ppa.launchpad.net precise Release [11.9 kB]
Get:38 http://archive.ubuntu.com precise-updates/main i386 Packages [96.5 kB]
Hit http://ppa.launchpad.net precise Release
Get:39 http://ppa.launchpad.net precise Release [11.9 kB]
Get:40 http://archive.ubuntu.com precise-updates/restricted i386 Packages [770 B]
Hit http://ppa.launchpad.net precise Release
Get:41 http://archive.ubuntu.com precise-updates/universe i386 Packages [27.7 kB]
Get:42 http://ppa.launchpad.net precise/main Sources [524 B]
Get:43 http://archive.ubuntu.com precise-updates/multiverse i386 Packages [1,393 B]
Get:44 http://ppa.launchpad.net precise/main i386 Packages [507 B]
Hit http://archive.ubuntu.com precise-updates/main TranslationIndex
Ign http://ppa.launchpad.net precise/main TranslationIndex
Hit http://archive.ubuntu.com precise-updates/multiverse TranslationIndex
Hit http://archive.ubuntu.com precise-updates/restricted TranslationIndex
Get:45 http://ppa.launchpad.net precise/main Sources [932 B]
Hit http://archive.ubuntu.com precise-updates/universe TranslationIndex
Get:46 http://ppa.launchpad.net precise/main i386 Packages [1,017 B]
Get:47 http://archive.ubuntu.com precise-backports/main i386 Packages [559 B]
Ign http://ppa.launchpad.net precise/main TranslationIndex
Get:48 http://archive.ubuntu.com precise-backports/restricted i386 Packages [14 B]
Get:49 http://archive.ubuntu.com precise-backports/universe i386 Packages [1,391 B]
Get:50 http://ppa.launchpad.net precise/main Sources [1,402 B]
Get:51 http://archive.ubuntu.com precise-backports/multiverse i386 Packages [14 B]
Hit http://archive.ubuntu.com precise-backports/main TranslationIndex
Get:52 http://ppa.launchpad.net precise/main i386 Packages [1,605 B]
Hit http://archive.ubuntu.com precise-backports/multiverse TranslationIndex
Ign http://ppa.launchpad.net precise/main TranslationIndex
Hit http://archive.ubuntu.com precise-backports/restricted TranslationIndex
Hit http://archive.ubuntu.com precise-backports/universe TranslationIndex
Hit http://archive.ubuntu.com precise/main Translation-en
Ign http://ppa.launchpad.net precise/main TranslationIndex
Hit http://archive.ubuntu.com precise/multiverse Translation-en
Get:53 http://ppa.launchpad.net precise/main Sources [931 B]
Hit http://archive.ubuntu.com precise/restricted Translation-en
Get:54 http://ppa.launchpad.net precise/main i386 Packages [1,079 B]
Hit http://archive.ubuntu.com precise/universe Translation-en
Ign http://ppa.launchpad.net precise/main TranslationIndex
Hit http://archive.ubuntu.com precise-updates/main Translation-en
Hit http://ppa.launchpad.net precise/main Sources
Hit http://archive.ubuntu.com precise-updates/multiverse Translation-en
Hit http://ppa.launchpad.net precise/main i386 Packages
Hit http://archive.ubuntu.com precise-updates/restricted Translation-en
Ign http://ppa.launchpad.net precise/main TranslationIndex
Hit http://archive.ubuntu.com precise-updates/universe Translation-en
Get:55 http://ppa.launchpad.net precise/main Sources [3,611 B]
Hit http://archive.ubuntu.com precise-backports/main Translation-en
Get:56 http://ppa.launchpad.net precise/main i386 Packages [2,468 B]
Hit http://archive.ubuntu.com precise-backports/multiverse Translation-en
Ign http://ppa.launchpad.net precise/main TranslationIndex
Hit http://archive.ubuntu.com precise-backports/restricted Translation-en
Hit http://archive.ubuntu.com precise-backports/universe Translation-en
Get:57 http://ppa.launchpad.net precise/main Sources [1,524 B]
Get:58 http://ppa.launchpad.net precise/main i386 Packages [2,719 B]
Ign http://ppa.launchpad.net precise/main TranslationIndex
Hit http://ppa.launchpad.net precise/main Sources
Hit http://ppa.launchpad.net precise/main i386 Packages
Ign http://ppa.launchpad.net precise/main TranslationIndex
Get:59 http://ppa.launchpad.net precise/main Sources [1,052 B]
Get:60 http://ppa.launchpad.net precise/main i386 Packages [1,388 B]
Ign http://ppa.launchpad.net precise/main TranslationIndex
Get:61 http://ppa.launchpad.net precise/main Sources [1,185 B]
Get:62 http://ppa.launchpad.net precise/main i386 Packages [1,698 B]
Ign http://ppa.launchpad.net precise/main TranslationIndex
Err http://ppa.launchpad.net precise/main Sources
404 Not Found
Err http://ppa.launchpad.net precise/main i386 Packages
404 Not Found
Ign http://ppa.launchpad.net precise/main Translation-en_US
Ign http://ppa.launchpad.net precise/main Translation-en
Ign http://ppa.launchpad.net precise/main Translation-en_US
Ign http://ppa.launchpad.net precise/main Translation-en
Ign http://ppa.launchpad.net precise/main Translation-en_US
Ign http://ppa.launchpad.net precise/main Translation-en
Ign http://ppa.launchpad.net precise/main Translation-en_US
Ign http://ppa.launchpad.net precise/main Translation-en
Ign http://ppa.launchpad.net precise/main Translation-en_US
Ign http://ppa.launchpad.net precise/main Translation-en
Ign http://ppa.launchpad.net precise/main Translation-en_US
Ign http://ppa.launchpad.net precise/main Translation-en
Ign http://ppa.launchpad.net precise/main Translation-en_US
Ign http://ppa.launchpad.net precise/main Translation-en
Ign http://ppa.launchpad.net precise/main Translation-en_US
Ign http://ppa.launchpad.net precise/main Translation-en
Ign http://ppa.launchpad.net precise/main Translation-en_US
Ign http://ppa.launchpad.net precise/main Translation-en
Ign http://ppa.launchpad.net precise/main Translation-en_US
Ign http://ppa.launchpad.net precise/main Translation-en
Ign http://ppa.launchpad.net precise/main Translation-en_US
Ign http://ppa.launchpad.net precise/main Translation-en
Fetched 6,699 kB in 15s (445 kB/s)
Reading package lists... Done
W: Failed to fetch http://dl.google.com/linux/talkplugin/deb/dists/stable/InRelease
W: Failed to fetch http://archive.canonical.com/ubuntu/dists/precise/partner/i18n/Translation-en_US Unable to connect to archive.canonical.com:http: [IP: 91.189.92.150 80]
W: Failed to fetch http://archive.canonical.com/ubuntu/dists/precise/partner/i18n/Translation-en Unable to connect to archive.canonical.com:http: [IP: 91.189.92.150 80]
W: Failed to fetch http://dl.google.com/linux/chrome/deb/dists/sta
答案1
是的，名称服务器更新确实有效，如果它确实有效，那么您可能已将 IP 设置更新为静态，并且您的服务器无法再解析 URL。
尝试上述操作，如果有效，请重新启动。如果重新启动后失败，请执行以下操作：
编辑模板文件resolv.conf。Ubuntu 服务器每次启动都会重建此文件。
sudo vi /etc/resolvconf/resolv.conf.d/tail
#add just these two lines >>
nameserver 8.8.8.8
nameserver 8.8.4.4
然后保存文件并重启服务：
sudo /etc/init.d/resolvconf restart
8.8.8.8和8.8.4.4只是 Google 的名称服务器。如果您愿意，您可以添加自己的 ISP。如果您不喜欢vi，请使用nano或vim。
我读了这篇文章才明白文章。所以，感谢他们提供的小费。
答案2
我刚刚找到答案这里。显然 apt 无法处理太多软件源，因此我可以通过取消选择除我需要访问的软件源之外的所有软件源来解决此问题。如果经常这样做，确实很麻烦，但总比什么都不做要好。摘自网站：
在“其他软件”选项卡中，禁用所有 PPA 存储库，只保留官方 Ubuntu 存储库。启用太多 PPA 存储库（非官方）可能会导致包管理器变得不稳定。
答案3
将该行添加nameserver 8.8.8.8到您的/etc/resolv.conf。
这会设置备用 DNS 服务器（Google 运行的公共 DNS 服务器），以防 DNS 出现问题。它与以下类似，但不完全相同：另一个答案（稍后发布，并提供了本质上相同的重新配置的不同方法）。
答案4
我遇到了同样的问题，我一直在检查，/etc/apt/sources.list但没能找到问题的根源。原来有一个/etc/apt/sources.list.d目录包含我过去添加的一堆文件。我在该目录中找到了无效文件，并将其删除。
apt-get 更新和升级现在运行正常。