Ao instalar o DansGuardian, conforme instruções no link a seguir:Filtragem de conteúdo Dansguardian com proxy transparente no Ubuntu 9.10 Karmic, defino o iptables usando sudo iptables -t nat -A OUTPUT -p tcp -m owner ! --uid-owner proxy --dport 80 -j REDIRECT --to-port 8080para que as solicitações da Web de saída feitas por qualquer pessoa que não seja o proxy sejam redirecionadas para o proxy. Salvei isso em /etc/init.d/tproxy, para tornar essas alterações permanentes.
Depois de fazer isso, apaguei DansGuardian, squid e iptables para refazer todo o procedimento, usandosudo apt autoremove dansguardian squid iptables
Sempre que executo sudo apt-get updateou sudo apt-get install ..agora, recebo o seguinte erro.
dell@dell-Inspiron-5558:/etc$ sudo apt-get update
Err:1 http://ppa.launchpad.net/webupd8team/sublime-text-3/ubuntu zesty InRelease
Could not connect to ppa.launchpad.net:80 (91.189.95.83). - connect (111: Connection refused)
Err:2 http://archive.canonical.com/ubuntu zesty InRelease
Could not connect to archive.canonical.com:80 (91.189.91.15). - connect (111: Connection refused) [IP: 91.189.91.15 80]
Err:3 http://in.old-releases.ubuntu.com/ubuntu zesty InRelease
Could not resolve 'in.old-releases.ubuntu.com'
Err:4 http://archive.ubuntu.com/ubuntu zesty InRelease
Could not connect to archive.ubuntu.com:80 (91.189.88.162). - connect (111: Connection refused) [IP: 91.189.88.162 80]
Err:5 http://in.old-releases.ubuntu.com/ubuntu zesty-updates InRelease
Could not resolve 'in.old-releases.ubuntu.com'
Err:6 http://in.old-releases.ubuntu.com/ubuntu zesty-backports InRelease
Could not resolve 'in.old-releases.ubuntu.com'
Err:7 http://in.old-releases.ubuntu.com/ubuntu zesty-security InRelease
Could not resolve 'in.old-releases.ubuntu.com'
Reading package lists... Done
W: Failed to fetch http://in.old-releases.ubuntu.com/ubuntu/dists/zesty/InRelease Could not resolve 'in.old-releases.ubuntu.com'
W: Failed to fetch http://in.old-releases.ubuntu.com/ubuntu/dists/zesty-updates/InRelease Could not resolve 'in.old-releases.ubuntu.com'
W: Failed to fetch http://in.old-releases.ubuntu.com/ubuntu/dists/zesty-backports/InRelease Could not resolve 'in.old-releases.ubuntu.com'
W: Failed to fetch http://archive.canonical.com/ubuntu/dists/zesty/InRelease Could not connect to archive.canonical.com:80 (91.189.91.15). - connect (111: Connection refused) [IP: 91.189.91.15 80]
W: Failed to fetch http://in.old-releases.ubuntu.com/ubuntu/dists/zesty-security/InRelease Could not resolve 'in.old-releases.ubuntu.com'
W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/zesty/InRelease Could not connect to archive.ubuntu.com:80 (91.189.88.162). - connect (111: Connection refused) [IP: 91.189.88.162 80]
W: Failed to fetch http://ppa.launchpad.net/webupd8team/sublime-text-3/ubuntu/dists/zesty/InRelease Could not connect to ppa.launchpad.net:80 (91.189.95.83). - connect (111: Connection refused)
W: Some index files failed to download. They have been ignored, or old ones used instead.
Os recursos mencionados, ou repositórios como arquivos do Ubuntu, também são inacessíveis através do navegador. Suspeito que isso se deva às configurações de IP que foram salvas antes da exclusão dos três arquivos mencionados.
Existe uma maneira de desfazer a alteração iptables -t nat -A OUTPUT -p tcp -m owner ! --uid-owner proxy --dport 80 -j REDIRECT --to-port 8080apesar de eu não ter mais o iptables?
Qualquer sugestão para fazer o mesmo ou qualquer diagnóstico alternativo é bem-vinda.