Instalando o postfix - Problemas com o apt-get

Question

Eu preciso instalar o postfix para enviar mensagens automáticas a partir do terminal do Ubuntu. Eu tentei com este comando:

sudo apt-get install postfix

Mas recebi os seguintes erros:

WARNING: The following packages cannot be authenticated!
postfix
Install these packages without verification? [y/N] y

Err http://us.archive.ubuntu.com/ubuntu/ trusty-updates/main postfix amd64 2.11.0-1ubuntu1   Could not resolve 'us.archive.ubuntu.com' E: Failed to fetch http://us.archive.ubuntu.com/ubuntu/pool/main/p/postfix/postfix_2.11.0-1ubuntu1_amd64.deb Could not resolve 'us.archive.ubuntu.com'

E: Unable to fetch some archives, maybe run apt-get update or try with
--fix-missing?

Eu também corri:

sudo apt-get update

e eu tenho isso:

Err http://extras.ubuntu.com trusty InRelease    
Err http://security.ubuntu.com trusty-security InRelease
Err http://security.ubuntu.com trusty-security Release.gpg
Could not resolve 'security.ubuntu.com'
Err http://extras.ubuntu.com trusty Release.gpg
Could not resolve 'extras.ubuntu.com'
Err http://us.archive.ubuntu.com trusty InRelease
Err http://us.archive.ubuntu.com trusty-updates InRelease
Err http://us.archive.ubuntu.com trusty-backports InRelease
Err http://us.archive.ubuntu.com trusty Release.gpg
Could not resolve 'us.archive.ubuntu.com'
Err http://us.archive.ubuntu.com trusty-updates Release.gpg
Could not resolve 'us.archive.ubuntu.com'
Err http://us.archive.ubuntu.com trusty-backports Release.gpg
Could not resolve 'us.archive.ubuntu.com'
Reading package lists... Done
W: Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/trusty/InRelease  
W: Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/trusty-updates/InRelease  

W: Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/trusty-backports/InRelease  

W: Failed to fetch http://security.ubuntu.com/ubuntu/dists/trusty-security/InRelease  

W: Failed to fetch http://extras.ubuntu.com/ubuntu/dists/trusty/InRelease  

W: Failed to fetch http://extras.ubuntu.com/ubuntu/dists/trusty/Release.gpg  Could not resolve 'extras.ubuntu.com'

W: Failed to fetch http://security.ubuntu.com/ubuntu/dists/trusty-security/Release.gpg   Could not resolve 'security.ubuntu.com'

W: Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/trusty/Release.gpg  Could not resolve 'us.archive.ubuntu.com'

W: Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/trusty-updates/Release.gpg   Could not resolve 'us.archive.ubuntu.com'

W: Failed to fetch http://us.archive.ubuntu.com/ubuntu/dists/trusty-backports/Release.gpg Could not resolve 'us.archive.ubuntu.com'

W: Some index files failed to download. They have been ignored, or old ones used instead.

Obrigado antecipadamente

P.S .: Minha versão do ubuntu é 14.04LTS e estou executando o VMware Workstation 12 Player.

    

Answer 1

Parece que você não tem uma conexão com a Internet. Se você tiver, tente

ping us.archive.ubuntu.com

Incase que não funciona, tente

host -v us.archive.ubuntu.com

Se houver algum erro na sua conexão DNS, eles aparecerão aqui.