Duplicate sources in Ubuntu 14.10's APT files, are they OK?

Question

So I was preparing to upgrade to ubuntu 15.04 and I was going through and cleaning things up and this is one of things that stood out to me.

W: Duplicate sources.list entry http://download.opensuse.org/repositories/home:/p_conrad:/coins/xUbuntu_14.10/  Packages (/var/lib/apt/lists/download.opensuse.org_repositories_home:_p%5fconrad:_coins_xUbuntu%5f14.10_Packages)
W: You may want to run apt-get update to correct these problems

Now updating with sudo apt-get update did nothing, so I went into vim to try to see if I could remove the referrals. I didn't spot anything, but here is the contents of directory.

archive.canonical.com_ubuntu_dists_utopic_partner_binary-amd64_Packages                         security.ubuntu.com_ubuntu_dists_vivid-security_restricted_source_Sources
archive.canonical.com_ubuntu_dists_utopic_partner_binary-i386_Packages                          security.ubuntu.com_ubuntu_dists_vivid-security_universe_binary-amd64_Packages
archive.canonical.com_ubuntu_dists_utopic_partner_i18n_Translation-en                           security.ubuntu.com_ubuntu_dists_vivid-security_universe_binary-i386_Packages
archive.canonical.com_ubuntu_dists_utopic_partner_source_Sources                                security.ubuntu.com_ubuntu_dists_vivid-security_universe_i18n_Translation-en
archive.canonical.com_ubuntu_dists_utopic_Release                                               security.ubuntu.com_ubuntu_dists_vivid-security_universe_source_Sources
archive.canonical.com_ubuntu_dists_utopic_Release.gpg                                           us.archive.ubuntu.com_ubuntu_dists_utopic-backports_main_binary-amd64_Packages
archive.canonical.com_ubuntu_dists_vivid_partner_binary-amd64_Packages                          us.archive.ubuntu.com_ubuntu_dists_utopic-backports_main_binary-i386_Packages
archive.canonical.com_ubuntu_dists_vivid_partner_binary-i386_Packages                           us.archive.ubuntu.com_ubuntu_dists_utopic-backports_main_i18n_Translation-en
archive.canonical.com_ubuntu_dists_vivid_partner_i18n_Translation-en                            us.archive.ubuntu.com_ubuntu_dists_utopic-backports_main_source_Sources
archive.canonical.com_ubuntu_dists_vivid_partner_source_Sources                                 us.archive.ubuntu.com_ubuntu_dists_utopic-backports_multiverse_binary-amd64_Packages
archive.canonical.com_ubuntu_dists_vivid_Release                                                us.archive.ubuntu.com_ubuntu_dists_utopic-backports_multiverse_binary-i386_Packages
archive.canonical.com_ubuntu_dists_vivid_Release.gpg                                            us.archive.ubuntu.com_ubuntu_dists_utopic-backports_multiverse_i18n_Translation-en

download.opensuse.org_repositories_home:_p%5fconrad:_coins_xUbuntu%5f14.10_Packages             us.archive.ubuntu.com_ubuntu_dists_utopic-backports_multiverse_source_Sources
download.opensuse.org_repositories_home:_p%5fconrad:_coins_xUbuntu%5f14.10_Release              us.archive.ubuntu.com_ubuntu_dists_utopic-backports_Release
download.opensuse.org_repositories_home:_p%5fconrad:_coins_xUbuntu%5f14.10_Release.gpg          us.archive.ubuntu.com_ubuntu_dists_utopic-backports_Release.gpg

Now this is what I think I should be looking for but this doesn't look like it has the duplicates.

download.videolan.org_pub_debian_stable_Packages                                                us.archive.ubuntu.com_ubuntu_dists_utopic-backports_restricted_binary-amd64_Packages
download.videolan.org_pub_debian_stable_Release                                                 us.archive.ubuntu.com_ubuntu_dists_utopic-backports_restricted_binary-i386_Packages
download.videolan.org_pub_debian_stable_Release.gpg                                             us.archive.ubuntu.com_ubuntu_dists_utopic-backports_restricted_i18n_Translation-en
download.videolan.org_pub_debian_stable_Sources                                                 us.archive.ubuntu.com_ubuntu_dists_utopic-backports_restricted_source_Sources

extras.ubuntu.com_ubuntu_dists_utopic_main_binary-amd64_Packages                                us.archive.ubuntu.com_ubuntu_dists_utopic-backports_universe_binary-amd64_Packages
extras.ubuntu.com_ubuntu_dists_utopic_main_binary-i386_Packages                                 us.archive.ubuntu.com_ubuntu_dists_utopic-backports_universe_binary-i386_Packages
extras.ubuntu.com_ubuntu_dists_utopic_main_source_Sources                                       us.archive.ubuntu.com_ubuntu_dists_utopic-backports_universe_i18n_Translation-en
extras.ubuntu.com_ubuntu_dists_utopic_Release                                                   us.archive.ubuntu.com_ubuntu_dists_utopic-backports_universe_source_Sources
extras.ubuntu.com_ubuntu_dists_utopic_Release.gpg                                               us.archive.ubuntu.com_ubuntu_dists_utopic_main_binary-amd64_Packages

liveusb.info_multisystem_depot_dists_all_main_binary-amd64_Packages                             us.archive.ubuntu.com_ubuntu_dists_utopic_main_binary-i386_Packages
liveusb.info_multisystem_depot_dists_all_main_binary-i386_Packages                              us.archive.ubuntu.com_ubuntu_dists_utopic_main_i18n_Translation-en
liveusb.info_multisystem_depot_dists_all_Release                                                us.archive.ubuntu.com_ubuntu_dists_utopic_main_source_Sources
liveusb.info_multisystem_depot_dists_all_Release.gpg                                            us.archive.ubuntu.com_ubuntu_dists_utopic_multiverse_binary-amd64_Packages

lock                                                                                            us.archive.ubuntu.com_ubuntu_dists_utopic_multiverse_binary-i386_Packages
partial                                                                                         us.archive.ubuntu.com_ubuntu_dists_utopic_multiverse_i18n_Translation-en

ppa.launchpad.net_i-nex-development-team_stable_ubuntu_dists_utopic_main_binary-amd64_Packages  us.archive.ubuntu.com_ubuntu_dists_utopic_multiverse_source_Sources
ppa.launchpad.net_i-nex-development-team_stable_ubuntu_dists_utopic_main_binary-i386_Packages   us.archive.ubuntu.com_ubuntu_dists_utopic_Release
ppa.launchpad.net_i-nex-development-team_stable_ubuntu_dists_utopic_Release                     us.archive.ubuntu.com_ubuntu_dists_utopic_Release.gpg
ppa.launchpad.net_i-nex-development-team_stable_ubuntu_dists_utopic_Release.gpg                 us.archive.ubuntu.com_ubuntu_dists_utopic_restricted_binary-amd64_Packages
ppa.launchpad.net_kubuntu-ppa_backports_ubuntu_dists_utopic_main_binary-amd64_Packages          us.archive.ubuntu.com_ubuntu_dists_utopic_restricted_binary-i386_Packages
ppa.launchpad.net_kubuntu-ppa_backports_ubuntu_dists_utopic_main_binary-i386_Packages           us.archive.ubuntu.com_ubuntu_dists_utopic_restricted_i18n_Translation-en
ppa.launchpad.net_kubuntu-ppa_backports_ubuntu_dists_utopic_main_i18n_Translation-en            us.archive.ubuntu.com_ubuntu_dists_utopic_restricted_source_Sources
ppa.launchpad.net_kubuntu-ppa_backports_ubuntu_dists_utopic_Release                             us.archive.ubuntu.com_ubuntu_dists_utopic_universe_binary-amd64_Packages
ppa.launchpad.net_kubuntu-ppa_backports_ubuntu_dists_utopic_Release.gpg                         us.archive.ubuntu.com_ubuntu_dists_utopic_universe_binary-i386_Packages
ppa.launchpad.net_kubuntu-ppa_next-backports_ubuntu_dists_utopic_main_binary-amd64_Packages     us.archive.ubuntu.com_ubuntu_dists_utopic_universe_i18n_Translation-en
ppa.launchpad.net_kubuntu-ppa_next-backports_ubuntu_dists_utopic_main_binary-i386_Packages      us.archive.ubuntu.com_ubuntu_dists_utopic_universe_source_Sources
ppa.launchpad.net_kubuntu-ppa_next-backports_ubuntu_dists_utopic_main_i18n_Translation-en       us.archive.ubuntu.com_ubuntu_dists_utopic-updates_main_binary-amd64_Packages
ppa.launchpad.net_kubuntu-ppa_next-backports_ubuntu_dists_utopic_Release                        us.archive.ubuntu.com_ubuntu_dists_utopic-updates_main_binary-i386_Packages
ppa.launchpad.net_kubuntu-ppa_next-backports_ubuntu_dists_utopic_Release.gpg                    us.archive.ubuntu.com_ubuntu_dists_utopic-updates_main_i18n_Translation-en
ppa.launchpad.net_n-muench_vlc_ubuntu_dists_utopic_main_binary-amd64_Packages                   us.archive.ubuntu.com_ubuntu_dists_utopic-updates_main_source_Sources
ppa.launchpad.net_n-muench_vlc_ubuntu_dists_utopic_main_binary-i386_Packages                    us.archive.ubuntu.com_ubuntu_dists_utopic-updates_multiverse_binary-amd64_Packages
ppa.launchpad.net_n-muench_vlc_ubuntu_dists_utopic_main_i18n_Translation-en                     us.archive.ubuntu.com_ubuntu_dists_utopic-updates_multiverse_binary-i386_Packages
ppa.launchpad.net_n-muench_vlc_ubuntu_dists_utopic_Release                                      us.archive.ubuntu.com_ubuntu_dists_utopic-updates_multiverse_i18n_Translation-en
ppa.launchpad.net_n-muench_vlc_ubuntu_dists_utopic_Release.gpg                                  us.archive.ubuntu.com_ubuntu_dists_utopic-updates_multiverse_source_Sources
ppa.launchpad.net_noobslab_indicators_ubuntu_dists_utopic_main_binary-amd64_Packages            us.archive.ubuntu.com_ubuntu_dists_utopic-updates_Release
ppa.launchpad.net_noobslab_indicators_ubuntu_dists_utopic_main_binary-i386_Packages             us.archive.ubuntu.com_ubuntu_dists_utopic-updates_Release.gpg
ppa.launchpad.net_noobslab_indicators_ubuntu_dists_utopic_Release                               us.archive.ubuntu.com_ubuntu_dists_utopic-updates_restricted_binary-amd64_Packages
ppa.launchpad.net_noobslab_indicators_ubuntu_dists_utopic_Release.gpg                           us.archive.ubuntu.com_ubuntu_dists_utopic-updates_restricted_binary-i386_Packages
ppa.launchpad.net_otto-kesselgulasch_gimp_ubuntu_dists_utopic_main_binary-amd64_Packages        us.archive.ubuntu.com_ubuntu_dists_utopic-updates_restricted_i18n_Translation-en
ppa.launchpad.net_otto-kesselgulasch_gimp_ubuntu_dists_utopic_main_binary-i386_Packages         us.archive.ubuntu.com_ubuntu_dists_utopic-updates_restricted_source_Sources
ppa.launchpad.net_otto-kesselgulasch_gimp_ubuntu_dists_utopic_main_i18n_Translation-en          us.archive.ubuntu.com_ubuntu_dists_utopic-updates_universe_binary-amd64_Packages
ppa.launchpad.net_otto-kesselgulasch_gimp_ubuntu_dists_utopic_Release                           us.archive.ubuntu.com_ubuntu_dists_utopic-updates_universe_binary-i386_Packages
ppa.launchpad.net_otto-kesselgulasch_gimp_ubuntu_dists_utopic_Release.gpg                       us.archive.ubuntu.com_ubuntu_dists_utopic-updates_universe_i18n_Translation-en
ppa.launchpad.net_spring_ppa_ubuntu_dists_utopic_main_binary-amd64_Packages                     us.archive.ubuntu.com_ubuntu_dists_utopic-updates_universe_source_Sources
ppa.launchpad.net_spring_ppa_ubuntu_dists_utopic_main_binary-i386_Packages                      us.archive.ubuntu.com_ubuntu_dists_vivid-backports_main_binary-amd64_Packages
ppa.launchpad.net_spring_ppa_ubuntu_dists_utopic_main_i18n_Translation-en                       us.archive.ubuntu.com_ubuntu_dists_vivid-backports_main_binary-i386_Packages
ppa.launchpad.net_spring_ppa_ubuntu_dists_utopic_Release                                        us.archive.ubuntu.com_ubuntu_dists_vivid-backports_main_i18n_Translation-en
ppa.launchpad.net_spring_ppa_ubuntu_dists_utopic_Release.gpg                                    us.archive.ubuntu.com_ubuntu_dists_vivid-backports_main_source_Sources
ppa.launchpad.net_ubuntu-wine_ppa_ubuntu_dists_utopic_main_binary-amd64_Packages                us.archive.ubuntu.com_ubuntu_dists_vivid-backports_multiverse_binary-amd64_Packages
ppa.launchpad.net_ubuntu-wine_ppa_ubuntu_dists_utopic_main_binary-i386_Packages                 us.archive.ubuntu.com_ubuntu_dists_vivid-backports_multiverse_binary-i386_Packages
ppa.launchpad.net_ubuntu-wine_ppa_ubuntu_dists_utopic_main_i18n_Translation-en                  us.archive.ubuntu.com_ubuntu_dists_vivid-backports_multiverse_i18n_Translation-en
ppa.launchpad.net_ubuntu-wine_ppa_ubuntu_dists_utopic_Release                                   us.archive.ubuntu.com_ubuntu_dists_vivid-backports_multiverse_source_Sources
ppa.launchpad.net_ubuntu-wine_ppa_ubuntu_dists_utopic_Release.gpg                               us.archive.ubuntu.com_ubuntu_dists_vivid-backports_Release
ppa.launchpad.net_webupd8team_tor-browser_ubuntu_dists_utopic_main_binary-amd64_Packages        us.archive.ubuntu.com_ubuntu_dists_vivid-backports_Release.gpg
ppa.launchpad.net_webupd8team_tor-browser_ubuntu_dists_utopic_main_binary-i386_Packages         us.archive.ubuntu.com_ubuntu_dists_vivid-backports_restricted_binary-amd64_Packages
ppa.launchpad.net_webupd8team_tor-browser_ubuntu_dists_utopic_main_i18n_Translation-en          us.archive.ubuntu.com_ubuntu_dists_vivid-backports_restricted_binary-i386_Packages
ppa.launchpad.net_webupd8team_tor-browser_ubuntu_dists_utopic_Release                           us.archive.ubuntu.com_ubuntu_dists_vivid-backports_restricted_i18n_Translation-en
ppa.launchpad.net_webupd8team_tor-browser_ubuntu_dists_utopic_Release.gpg                       us.archive.ubuntu.com_ubuntu_dists_vivid-backports_restricted_source_Sources
ppa.launchpad.net_wfg_0ad_ubuntu_dists_utopic_main_binary-amd64_Packages                        us.archive.ubuntu.com_ubuntu_dists_vivid-backports_universe_binary-amd64_Packages
ppa.launchpad.net_wfg_0ad_ubuntu_dists_utopic_main_binary-i386_Packages                         us.archive.ubuntu.com_ubuntu_dists_vivid-backports_universe_binary-i386_Packages
ppa.launchpad.net_wfg_0ad_ubuntu_dists_utopic_main_i18n_Translation-en                          us.archive.ubuntu.com_ubuntu_dists_vivid-backports_universe_i18n_Translation-en
ppa.launchpad.net_wfg_0ad_ubuntu_dists_utopic_Release                                           us.archive.ubuntu.com_ubuntu_dists_vivid-backports_universe_source_Sources
ppa.launchpad.net_wfg_0ad_ubuntu_dists_utopic_Release.gpg                                       us.archive.ubuntu.com_ubuntu_dists_vivid_main_binary-amd64_Packages
ppa.launchpad.net_xorg-edgers_ppa_ubuntu_dists_utopic_main_binary-amd64_Packages                us.archive.ubuntu.com_ubuntu_dists_vivid_main_binary-i386_Packages
ppa.launchpad.net_xorg-edgers_ppa_ubuntu_dists_utopic_main_binary-i386_Packages                 us.archive.ubuntu.com_ubuntu_dists_vivid_main_i18n_Translation-en
ppa.launchpad.net_xorg-edgers_ppa_ubuntu_dists_utopic_main_i18n_Translation-en                  us.archive.ubuntu.com_ubuntu_dists_vivid_main_source_Sources
ppa.launchpad.net_xorg-edgers_ppa_ubuntu_dists_utopic_Release                                   us.archive.ubuntu.com_ubuntu_dists_vivid_multiverse_binary-amd64_Packages
ppa.launchpad.net_xorg-edgers_ppa_ubuntu_dists_utopic_Release.gpg                               us.archive.ubuntu.com_ubuntu_dists_vivid_multiverse_binary-i386_Packages

security.ubuntu.com_ubuntu_dists_utopic-security_main_binary-amd64_Packages                     us.archive.ubuntu.com_ubuntu_dists_vivid_multiverse_i18n_Translation-en
security.ubuntu.com_ubuntu_dists_utopic-security_main_binary-i386_Packages                      us.archive.ubuntu.com_ubuntu_dists_vivid_multiverse_source_Sources
security.ubuntu.com_ubuntu_dists_utopic-security_main_i18n_Translation-en                       us.archive.ubuntu.com_ubuntu_dists_vivid_Release
security.ubuntu.com_ubuntu_dists_utopic-security_main_source_Sources                            us.archive.ubuntu.com_ubuntu_dists_vivid_Release.gpg
security.ubuntu.com_ubuntu_dists_utopic-security_multiverse_binary-amd64_Packages               us.archive.ubuntu.com_ubuntu_dists_vivid_restricted_binary-amd64_Packages
security.ubuntu.com_ubuntu_dists_utopic-security_multiverse_binary-i386_Packages                us.archive.ubuntu.com_ubuntu_dists_vivid_restricted_binary-i386_Packages
security.ubuntu.com_ubuntu_dists_utopic-security_multiverse_i18n_Translation-en                 us.archive.ubuntu.com_ubuntu_dists_vivid_restricted_i18n_Translation-en
security.ubuntu.com_ubuntu_dists_utopic-security_multiverse_source_Sources                      us.archive.ubuntu.com_ubuntu_dists_vivid_restricted_source_Sources
security.ubuntu.com_ubuntu_dists_utopic-security_Release                                        us.archive.ubuntu.com_ubuntu_dists_vivid_universe_binary-amd64_Packages
security.ubuntu.com_ubuntu_dists_utopic-security_Release.gpg                                    us.archive.ubuntu.com_ubuntu_dists_vivid_universe_binary-i386_Packages
security.ubuntu.com_ubuntu_dists_utopic-security_restricted_binary-amd64_Packages               us.archive.ubuntu.com_ubuntu_dists_vivid_universe_i18n_Translation-en
security.ubuntu.com_ubuntu_dists_utopic-security_restricted_binary-i386_Packages                us.archive.ubuntu.com_ubuntu_dists_vivid_universe_source_Sources
security.ubuntu.com_ubuntu_dists_utopic-security_restricted_i18n_Translation-en                 us.archive.ubuntu.com_ubuntu_dists_vivid-updates_main_binary-amd64_Packages
security.ubuntu.com_ubuntu_dists_utopic-security_restricted_source_Sources                      us.archive.ubuntu.com_ubuntu_dists_vivid-updates_main_binary-i386_Packages
security.ubuntu.com_ubuntu_dists_utopic-security_universe_binary-amd64_Packages                 us.archive.ubuntu.com_ubuntu_dists_vivid-updates_main_i18n_Translation-en
security.ubuntu.com_ubuntu_dists_utopic-security_universe_binary-i386_Packages                  us.archive.ubuntu.com_ubuntu_dists_vivid-updates_main_source_Sources
security.ubuntu.com_ubuntu_dists_utopic-security_universe_i18n_Translation-en                   us.archive.ubuntu.com_ubuntu_dists_vivid-updates_multiverse_binary-amd64_Packages
security.ubuntu.com_ubuntu_dists_utopic-security_universe_source_Sources                        us.archive.ubuntu.com_ubuntu_dists_vivid-updates_multiverse_binary-i386_Packages
security.ubuntu.com_ubuntu_dists_vivid-security_main_binary-amd64_Packages                      us.archive.ubuntu.com_ubuntu_dists_vivid-updates_multiverse_i18n_Translation-en
security.ubuntu.com_ubuntu_dists_vivid-security_main_binary-i386_Packages                       us.archive.ubuntu.com_ubuntu_dists_vivid-updates_multiverse_source_Sources
security.ubuntu.com_ubuntu_dists_vivid-security_main_i18n_Translation-en                        us.archive.ubuntu.com_ubuntu_dists_vivid-updates_Release
security.ubuntu.com_ubuntu_dists_vivid-security_main_source_Sources                             us.archive.ubuntu.com_ubuntu_dists_vivid-updates_Release.gpg
security.ubuntu.com_ubuntu_dists_vivid-security_multiverse_binary-amd64_Packages                us.archive.ubuntu.com_ubuntu_dists_vivid-updates_restricted_binary-amd64_Packages
security.ubuntu.com_ubuntu_dists_vivid-security_multiverse_binary-i386_Packages                 us.archive.ubuntu.com_ubuntu_dists_vivid-updates_restricted_binary-i386_Packages
security.ubuntu.com_ubuntu_dists_vivid-security_multiverse_i18n_Translation-en                  us.archive.ubuntu.com_ubuntu_dists_vivid-updates_restricted_i18n_Translation-en
security.ubuntu.com_ubuntu_dists_vivid-security_multiverse_source_Sources                       us.archive.ubuntu.com_ubuntu_dists_vivid-updates_restricted_source_Sources
security.ubuntu.com_ubuntu_dists_vivid-security_Release                                         us.archive.ubuntu.com_ubuntu_dists_vivid-updates_universe_binary-amd64_Packages
security.ubuntu.com_ubuntu_dists_vivid-security_Release.gpg                                     us.archive.ubuntu.com_ubuntu_dists_vivid-updates_universe_binary-i386_Packages
security.ubuntu.com_ubuntu_dists_vivid-security_restricted_binary-amd64_Packages                us.archive.ubuntu.com_ubuntu_dists_vivid-updates_universe_i18n_Translation-en
security.ubuntu.com_ubuntu_dists_vivid-security_restricted_binary-i386_Packages                 us.archive.ubuntu.com_ubuntu_dists_vivid-updates_universe_source_Sources
security.ubuntu.com_ubuntu_dists_vivid-security_restricted_i18n_Translation-en

Now, I installed this: sudo apt-get install nfs-kernel-server from here: https://askubuntu.com/questions/583279/unable-to-correct-problems-you-have-held-broken-packages-while-installing-nfs-s

Answer 1

Duplicate source.list entries aren't a big problem, just a small performance hit.

The message is misleading: apt-get update alone won't eliminate duplicate entries. You need to edit the source.list files: /etc/apt/sources.list and the files in /etc/apt/sources.list.d. Look for entries for the repository mentioned in the error message and remove one of the duplicates. Then run apt-get update.

Answer 2

I would start out by manually trying the instructions here: How do I add a line to my /etc/apt/sources.list?

Here's how I edited mine:

$ ls /etc/apt 
apt.conf.d  preferences  preferences.d  sources.list  sources.list.d sources.list.save  trustdb.gpg  trusted.gpg  trusted.gpg~  trusted.gpg.d
$ vi /etc/apt/sources.list

There's further information here: https://wiki.debian.org/SourcesList

Once you have a feel for how that works, I would try using the software here to generate a replacement sources.list file: http://repogen.simplylinux.ch/.