qDup is designed to work with linux.
We do not have Windows or Mac computers available for testing so the tool is not expected to run from those operating systems.
qDup uses ssh to connect with other computers. If you do not have ssh running on another computer you can start ssh on your computer.
#> sudo systemctl start sshd
If your user does not have sudo permissions you will need change to the root user then start sshd
#> su
Password:
#> systemctl start sshd
Test that ssh is running by trying to ssh to localhost
#> ssh localhost
Password:
Last login: Thu Sep 15 10:00:00 2022 from 192.168.0.1
The ssh
command works with just a computer name but qDup needs a username along with the name of the computer.
#> whoami
testuser
qDup can work username and password but it more secure to use key based authentication. First, check if you already have keys
#> ls -al ~/.ssh
-rw-------. 1 testuser testuser 1675 Sep 15 2022 id_rsa
-rw-r--r--. 1 testuser testuser 398 Sep 15 2020 id_rsa.pub
...
If you want to use your existing keys then you need to remember the file name. We are going to create temporary keys.
First, if ls -al
gave an error No such file or directory
then you need to create the .ssh directory
#> mkdir ~/.ssh
Then create a new key
#> ssh-keygen -f ~/.ssh/qdup -t ecdsa
Generating public/private ecdsa key pair.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/testuser/.ssh/qdup
Your public key has been saved in /home/testuser/.ssh/qdup.pub
The key fingerprint is:
SHA256:... testuser@localhost
...
The new key needs to be added to ~/.ssh/authorized_keys
but that file may not exist.
If the previous ls -al ~/.ssh
did not include a file named authorized_keys
then create one and give it the correct file permissions
#> touch ~/.ssh/authorized_keys
#> chmod g-w ~/.ssh/authorized_keys
Add the new qdup
key to the list of keys.
#> (cat ~/.ssh/qdup.pub; echo) >> ~/.ssh/authorized_keys
The ssh
command should work with your user’s name (from whoami
) and the localhost
computer name without being asked for a password
#> ssh testuser@localhost
Last login: Thu Sep 15 10:01:00 2022 from 192.168.0.1
qDup is distributed as a java executable jar (java’s version of a zip file). You need to have Java 17 or higher installed to run qDup. We can check for java
#> java -version
openjdk version "17.0.13" 2024-10-15
OpenJDK Runtime Environment Temurin-17.0.13+11 (build 17.0.13+11)
OpenJDK 64-Bit Server VM Temurin-17.0.13+11 (build 17.0.13+11, mixed mode, sharing)
if you see bash: java: command not found…
then install [Java 17](https://adoptopenjdk.net/) or higher.
At this point you should have the necessary tools to run qDup. Try the hello world tutorial to get started running qDup.