Estive com Problemas ao atualizar um host dentro de um container Docker, resolvi atualizando a Souce.list que fica em /etc/apt
### See http://help.ubuntu.com/community/UpgradeNotes.
### Default Repos.
deb http://br.archive.ubuntu.com/ubuntu/ trusty main restricted universe multiverse
deb-src http://br.archive.ubuntu.com/ubuntu/ trusty main restricted universe multiverse
### Security Updates.
deb http://security.ubuntu.com/ubuntu trusty-security main restricted universe multiverse
deb-src http://security.ubuntu.com/ubuntu trusty-security main restricted universe multiverse
### Major bug fix updates.
deb http://br.archive.ubuntu.com/ubuntu/ trusty-updates main restricted universe multiverse
deb-src http://br.archive.ubuntu.com/ubuntu/ trusty-updates main restricted universe multiverse
### Backports.
deb http://br.archive.ubuntu.com/ubuntu/ trusty-backports main restricted universe multiverse
deb-src http://br.archive.ubuntu.com/ubuntu/ trusty-backports main restricted universe multiverse
### Partner's repository.
deb http://archive.canonical.com/ubuntu trusty partner
deb-src http://archive.canonical.com/ubuntu trusty partner
### Extras.
deb http://extras.ubuntu.com/ubuntu trusty main
deb-src http://extras.ubuntu.com/ubuntu trusty main
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