apt-get update 出现 这种错误
Reading package lists… Done
W: There is no public key available for the following key IDs:
7638D0442B90D010
W: There is no public key available for the following key IDs:
7638D0442B90D010
W: There is no public key available for the following key IDs:
9D6D8F6BC857C906
解决方法
apt-get install debian-keyring debian-archive-keyring
apt-get update
碳粉清零：
1、打开前盖
2、按清除键显示跟换硒鼓不理它，马上再按“启用”键，然后马上按“00”。 过几秒就可以关前盖 就可以了
硒鼓清零：
1、打开前盖
2、按清除键显示跟换硒鼓
1是 2否 按1
过几秒就可以关前盖就可以了
Depends: init-system-helpers (>= 1.18~) but it is not installable
E: Unable to correct problems, you have held broken packages.
Working on debian wheezy…
I added backports to my apt repo “deb http://ftp.de.debian.org/debian wheezy-backports main” and performed a “apt-get update”. Afterwards, the apt-get install docker-engine completed fine.
Personally, I’m leaving backports commented out for now but in my conf as a reminder…
In Red Hat based distributions such as Fedora and CentOS, make use of a script called ‘chkconfig‘ to enable and disable the running services in Linux.
For example, lets disable the Apache web server at the system startup.
[avishek@tecmint]# chkconfig httpd off
[avishek@tecmint]# chkconfig httpd –del
In Debian based distributions such as Ubuntu, Linux Mint and other Debian based distributions use a script called update-rc.d.
For example, to disable the Apache service at the system startup execute the following command. Here ‘-f’ option stands for force is mandatory.
[avishek@tecmint]# update-rc.d -f a
