You can customize the logo of Mac OS Client according to your requirement. The format of the logo must meet the following requirements:
Image format: png, jpg, gif
Resolution: 400x400px
Maximum file size: 100Kb
To customize the logo, perform the following steps:
Open the configuration file /Library/Security/SecurityAgentPlugins/aucore_login.bundle/Contents/etc/aucore_login.conf.
If the file does not exist, create a new file.
Specify the path of the folder where the image file is stored, in the following format:
logo_path: /Users/<username>/<path_of_the_file>/<file_name>.png
Save the configuration file aucore_login.conf.
Restart the computer.