Howto Fix Error "...no public key available..." on Debian Wheezy

If when running an apt-get update on your Debian Wheezy you are getting an error similar to this one:

W: There is no public key available for the following key IDs:
7638D0442B90D010

Here is what you should do:
apt-get install debian-keyring debian-archive-keyring
apt-get update

Installare Tomcat 8 in Debian 8 dal Repository

Debian 8 ha un package stable per Apache Tomcat 8. Per installarlo eseguire questo comando:
apt-get install tomcat8

Dopo averlo installato, se si sta usando Oracle Java 8, non partirà a causa di un bug su /etc/init.d/tomcat8, perciò modificare questo file ed aggiungere questa riga dentro la funzione find_jdks()
/usr/lib/jvm/java-${java_version}-oracle

Install Tomcat 8 in Debian 8 via Repo

Debian 8 has stable package for Apache Tomcat 8. To install it just execute this command:
apt-get install tomcat8

After installing it, if you're using Oracle Java 8, it will not start because of a bug on /etc/init.d/tomcat8, so edit this file and add this line on the function find_jdks()
/usr/lib/jvm/java-${java_version}-oracle

Installare Oracle Java 8 in Debian dal Repository

Per aggiungere il repository  WebUpd8 Oracle Java PPA ed installare Oracle Java 8 in Debian, usare i seguenti comandi:
echo "deb http://ppa.launchpad.net/webupd8team/java/ubuntu trusty main" | tee /etc/apt/sources.list.d/webupd8team-java.list
echo "deb-src http://ppa.launchpad.net/webupd8team/java/ubuntu trusty main" | tee -a /etc/apt/sources.list.d/webupd8team-java.list
apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys EEA14886
apt-get update
apt-get install oracle-java8-installer

Tutto qui, Oracle Java 8 dovrebbe ora essere installato e si dovrebbero ottenere gli aggiornamenti automatici per le versioni future di Oracle Java 8, sotto Debian.

Puoi controllare la versione di Java sul tuo sistema con questo comando:
java -version

C'è un package nel repository che imposta automaticamente le variabili d'ambiente di Java 8 ed imposta JDK8 come JDK di default. Per installarlo, usare il seguente comando:
apt-get install oracle-java8-set-default
source /etc/profile.d/jdk.sh

Install Oracle Java 8 in Debian via Repo

To add the WebUpd8 Oracle Java PPA repository and install Oracle Java 8 in Debian, use the following commands:
echo "deb http://ppa.launchpad.net/webupd8team/java/ubuntu trusty main" | tee /etc/apt/sources.list.d/webupd8team-java.list
echo "deb-src http://ppa.launchpad.net/webupd8team/java/ubuntu trusty main" | tee -a /etc/apt/sources.list.d/webupd8team-java.list
apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys EEA14886
apt-get update
apt-get install oracle-java8-installer

And that's it, Oracle Java 8 should now be installed and you should get automatic updates for future Oracle Java 8 versions, under Debian.

You can check out the Java version on your system by using these commands:
java -version

There is a package in repository that automatically sets the Java 8 environment variables and sets JDK8 as the default JDK. To install it, use the following command:
apt-get install oracle-java8-set-default
source /etc/profile.d/jdk.sh

Installare MySQL 5.6 su Debian 7

Aggiungi il Repo
wget http://repo.mysql.com/mysql-apt-config_0.3.5-1debian7_all.deb
dpkg -i mysql-apt-config_0.3.5-1debian7_all.deb

Verrà creato un file /etc/apt/sources.list.d/mysql.list che conterrà delle righe simili alle seguenti:
deb http://repo.mysql.com/apt/debian/ wheezy mysql-5.6
deb-src http://repo.mysql.com/apt/debian/ wheezy mysql-5.6

Installa MySql 5.6
apt-get update
apt-get install mysql-server-5.6

Install MySQL 5.6 on Debian 7

Add the Repo
wget http://repo.mysql.com/mysql-apt-config_0.3.5-1debian7_all.deb
dpkg -i mysql-apt-config_0.3.5-1debian7_all.deb

The above package will create a file /etc/apt/sources.list.d/mysql.list which will contain lines like these or similar:
deb http://repo.mysql.com/apt/debian/ wheezy mysql-5.6
deb-src http://repo.mysql.com/apt/debian/ wheezy mysql-5.6

Install MySql 5.6
apt-get update
apt-get install mysql-server-5.6