Estou tentando usar o cron para automatizar as atualizações do meu sistema. Você pode ver meus crontab, comandos e erros resultantes abaixo.
Quando executo o upgrades.sh como root, o script é executado corretamente. Quando o cron o executa, apt-get -y update não é executado, mas aptitude -y safe-upgrade falha. Eu estou supondo este erro: debconf: (This frontend requires a controlling tty.) é porque há uma atualização do kernel que por sua vez atualiza o grub, o que requer meu explicitamente dizendo que não há problema em sobrescrever /boot/grub/menu.lst . Mas eu não entendo os erros do caminho. E eu gostaria das atualizações que não exigem minha supervisão.
Eu li através desta esta questão e ainda é inaceitável a solução de unattended-upgrades , e eu posso acabar usando mas porque não posso usar o cron? Parece que deve ser muito simples e mais linuxy.
root@daedalus:~/bin# crontab -l
# m h dom mon dow command
45 06 * * * ~/bin/upgrades.sh
root@daedalus:~/bin# cat upgrades.sh
#!/bin/bash
/usr/bin/apt-get -y update
/usr/bin/aptitude -y safe-upgrade
debconf: unable to initialize frontend: Dialog
debconf: (TERM is not set, so the dialog frontend is not usable.)
debconf: falling back to frontend: Readline
debconf: unable to initialize frontend: Readline
debconf: (This frontend requires a controlling tty.)
debconf: falling back to frontend: Teletype
dpkg-preconfigure: unable to re-open stdin:
Fetched 37.6MB in 4min 23s (143kB/s)
dpkg: warning: 'ldconfig' not found on PATH.
dpkg: warning: 'start-stop-daemon' not found on PATH.
dpkg: warning: 'update-rc.d' not found on PATH.
dpkg: 3 expected program(s) not found on PATH.
NB: root's PATH should usually contain /usr/local/sbin, /usr/sbin and /sbin.
E: Sub-process /usr/bin/dpkg returned an error code (2)
A package failed to install. Trying to recover:
dpkg: warning: 'ldconfig' not found on PATH.
dpkg: warning: 'start-stop-daemon' not found on PATH.
dpkg: warning: 'update-rc.d' not found on PATH.
dpkg: 3 expected program(s) not found on PATH.
NB: root's PATH should usually contain /usr/local/sbin, /usr/sbin and /sbin.
Reading package lists...
Building dependency tree...
Reading state information...
Reading extended state information...
Initializing package states...
Writing extended state information...
As mensagens informam que sua variável de ambiente PATH está errada.
Tente adicionar
PATH=/usr/bin:/bin:/usr/sbin:/sbin
para o topo do seu crontab .
Ou você pode colocar a mesma linha PATH como a segunda linha de ~/bin/upgrades.sh . Dessa forma, seu teste na linha de comando e seu teste em crontab devem produzir os mesmos resultados.
Embora seu problema principal já tenha sido respondido, parece que você está recebendo avisos do debconf porque você está executando o apt-get sem um tty interativo. Para se livrar dessas mensagens, você pode definir essa variável de ambiente:
DEBIAN_FRONTEND=noninteractive
Existe uma página wiki da comunidade: Razão pela qual o crontab não funciona . Nesse caso, parece que a causa são as variáveis de ambiente limitadas do cron. Você pode executar isso a partir de um script de shell em /etc/cron.daily?
De CronHowto :
Dependendo dos comandos que estão sendo executados, você pode precisar expandir os usuários root Variável PATH, colocando o seguinte linha na parte superior do arquivo crontab:
CAMINHO = / usr / sbin: / usr / bin: / sbin: / bin
Mas na verdade, tudo parece estar bem fazendo o mesmo que você .... De onde você tirou esses erros?
CRONTAB:
root@PORTATIL:/var/log$ crontab -l
* * */2 * * /usr/share/myupdate.sh > /var/log/myupdate.log
SCRIPT:
root@PORTATIL:/etc# cat /usr/share/myupdate.sh
#!/bin/bash
#Testing updates
apt-get update -y
apt-get upgrade -y
LOG:
root@PORTATIL:/etc# cat /var/log/myupdate.log
Hit http://security.ubuntu.com lucid-security Release.gpg
Hit http://archive.canonical.com lucid Release.gpg
Hit http://archive.canonical.com lucid Release.gpg
Hit http://packages.medibuntu.org lucid Release.gpg
Get:1 http://dl.google.com stable Release.gpg [197B]
Hit http://ppa.launchpad.net lucid Release.gpg
Hit http://ppa.launchpad.net lucid Release.gpg
Hit http://ppa.launchpad.net lucid Release.gpg
Hit http://security.ubuntu.com lucid-security Release
Hit http://badgerports.org lucid Release.gpg
Hit http://archive.canonical.com lucid Release
Hit http://ppa.launchpad.net lucid Release.gpg
Hit http://ppa.launchpad.net maverick Release.gpg
Hit http://ppa.launchpad.net lucid Release.gpg
Hit http://ppa.launchpad.net lucid Release.gpg
Hit http://ppa.launchpad.net lucid Release.gpg
Get:2 http://dl.google.com stable Release [1347B]
Hit http://security.ubuntu.com lucid-security/main Packages
Hit http://ppa.launchpad.net lucid Release
Hit http://ppa.launchpad.net lucid Release
Hit http://packages.medibuntu.org lucid Release
Hit http://download.virtualbox.org lucid Release.gpg
Hit http://archive.canonical.com lucid Release
Hit http://linux.dropbox.com lucid Release.gpg
Get:3 http://dl.google.com stable/main Packages [1110B]
Hit http://security.ubuntu.com lucid-security/restricted Packages
Hit http://security.ubuntu.com lucid-security/main Sources
Hit http://security.ubuntu.com lucid-security/restricted Sources
Hit http://security.ubuntu.com lucid-security/universe Packages
Hit http://security.ubuntu.com lucid-security/universe Sources
Hit http://ppa.launchpad.net lucid Release
Hit http://ppa.launchpad.net lucid Release
Hit http://ppa.launchpad.net maverick Release
Hit http://ppa.launchpad.net lucid Release
Hit http://ppa.launchpad.net lucid Release
Hit http://badgerports.org lucid Release
Hit http://archive.canonical.com lucid/partner Packages
Hit http://security.ubuntu.com lucid-security/multiverse Packages
Hit http://security.ubuntu.com lucid-security/multiverse Sources
Hit http://ppa.launchpad.net lucid Release
Hit http://packages.medibuntu.org lucid/free Packages
Hit http://download.virtualbox.org lucid Release
Hit http://es.archive.ubuntu.com lucid Release.gpg
Hit http://linux.dropbox.com lucid Release
Hit http://archive.canonical.com lucid/partner Packages
Hit http://ppa.launchpad.net lucid/main Packages
Hit http://ppa.launchpad.net lucid/main Packages
Hit http://es.archive.ubuntu.com lucid-updates Release.gpg
Hit http://badgerports.org lucid/main Packages
Hit http://ppa.launchpad.net lucid/main Packages
Hit http://ppa.launchpad.net lucid/main Packages
Hit http://ppa.launchpad.net maverick/main Packages
Hit http://ppa.launchpad.net lucid/main Packages
Hit http://ppa.launchpad.net lucid/main Packages
Hit http://packages.medibuntu.org lucid/non-free Packages
Hit http://linux.dropbox.com lucid/main Packages
Hit http://es.archive.ubuntu.com lucid Release
Hit http://download.virtualbox.org lucid/contrib Packages
Hit http://ppa.launchpad.net lucid/main Packages
Hit http://es.archive.ubuntu.com lucid-updates Release
Hit http://es.archive.ubuntu.com lucid/main Packages
Hit http://es.archive.ubuntu.com lucid/restricted Packages
Hit http://es.archive.ubuntu.com lucid/main Sources
Hit http://es.archive.ubuntu.com lucid/restricted Sources
Hit http://es.archive.ubuntu.com lucid/universe Packages
Hit http://es.archive.ubuntu.com lucid/universe Sources
Hit http://es.archive.ubuntu.com lucid/multiverse Packages
Hit http://es.archive.ubuntu.com lucid/multiverse Sources
Hit http://es.archive.ubuntu.com lucid-updates/main Packages
Hit http://es.archive.ubuntu.com lucid-updates/restricted Packages
Hit http://es.archive.ubuntu.com lucid-updates/main Sources
Hit http://es.archive.ubuntu.com lucid-updates/restricted Sources
Hit http://es.archive.ubuntu.com lucid-updates/universe Packages
Hit http://es.archive.ubuntu.com lucid-updates/universe Sources
Hit http://es.archive.ubuntu.com lucid-updates/multiverse Packages
Hit http://es.archive.ubuntu.com lucid-updates/multiverse Sources
Fetched 2654B in 1s (1628B/s)
Reading package lists...
Reading package lists...
Building dependency tree...
Reading state information...
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.