Versions this guide is based on:

EVE Image Name Downloaded Filename Version vCPUs vRAM
veos-4.14.0F vEOS-4.14.0F.vmdk
Aboot-veos-serial-2.1.0.iso
4.14.0F 1 2048

Other versions should also be supported following bellow's procedure.

Upload the downloaded image to the EVE using for example FileZilla or WinSCP. Then login as root using SSH protocol and convert it:

mkdir tmp
cd tmp
/opt/qemu/bin/qemu-img convert -f vmdk -O qcow2 ../vEOS-4.14.0F.vmdk hda.qcow2

Create the folder for HDD image and move it:

mkdir -p /opt/unetlab/addons/qemu/veos-4.14.0F
mv hda.qcow2 /opt/unetlab/addons/qemu/veos-4.14.0F
mv Aboot-veos-serial-2.1.0.iso /opt/unetlab/addons/qemu/veos-4.14.0F/cdrom.iso

Clean and fix permissions:

cd ..
rm -rf tmp
/opt/unetlab/wrappers/unl_wrapper -a fixpermissions

Default username is admin without password.