Old version of rootfs

Hello I am trying to build old version of PYNQ v2.3.
However I cannot find rootfs for v2.3, only 2.6.
Do you know where can I get the rootfs file?

Image files for the supported boards are available through our tagged Github release. If you want board-agnostic images, v2.3 predates us moving to that flow so they were never created. If you want to support a custom board you are best off starting from one of the above-linked images and working out how to modify the boot files to support your board. This isn’t supported though.