Unlike the majority of CD/DVD image formats, the PowerISO's .daa format allows advanced features such as file compression, password protection, encryption and the ability to split files in to multiple volumes. Due to these advanced features, PowerISO is the only software package that can read .daa files.
But it is very simple to convert DAA to ISO in linux. You just need an utility called daa2iso.
Install it on a RPM based system using ’sudo yum -y install daa2iso’
or on a debian based system using ’sudo apt-get install daa2iso.
And to use the utility, just type the following: daa2iso source-file.daa dest-file.iso