1- Run this command in Terminal:

sudo apt install default-jre

When asked "Do you want to continue?", press Y and enter to complete the installation.

2- Download and install the e-signature drivers from https://kamusm.bilgem.tubitak.gov.tr/islemler/surucu_yukleme_servisi/.

3- Download the current DSClient (latest version: 1.5.5) for Ubuntu Linux from here, and for Debian Linux from here. After extracting the files you have downloaded, go to the SetupFiles folder, then right click on the folder and select "Open in Terminal".

IMPORTANT NOTE: For users with DSClient versions earlier than 1.5.5, in order for them to e-sign without any issues, users need to either update to 1.5.5, or follow the provided steps in https://faq.cc.metu.edu.tr/faq/ebys-dsclient-license-file-change to change the license file.

In the terminal that opened, for Ubuntu run the command,

bash DSClientLinux.sh

and for Debian run the command,

bash DSClientDebian.sh

The installation is complete.

If you still have problems while using e-signatures in EBYS after following the steps above, or have other questions about e-signatures, you can look at the frequently asked questions in https://faq.cc.metu.edu.tr/groups/e-signature.
Questions about EBYS can be directed to ebys-destek@metu.edu.tr.