first you need to download a image (iso..etc Kali Linux,debian..or whatever you wnt!!!...if you have debian the iso must be debian two,this is not working if you mix ubuntu with debian..)
Rename the iso to binary.iso and save it on the desktop ...
#open a terminal
# switch to root directory
cd /
# create a work folder
mkdir work
# change to the work folder
cd work
# move your previously downloaded/created live image (binary.iso) to the work folder
mv /home/YOURUSERNAME/Desktop/binary.iso /work
#extract binary.iso to use it for our custom image
mkdir iso
mkdir temp
mount binary.iso temp/ -o loop
rsync -a temp/ iso/
umount temp/
rm -rf temp/
# remove the old squash from the unpacked iso since we will build a new one from our filesystem
rm iso/live/filesystem.squashfs
# make a directory to contain a copy of the filesystem
mkdir myfs
# copy our system to the myfs folder, exclude a few odds and ends
# exclude other items as needed
rsync -a / myfs/ --exclude=/{work,cdrom,mnt,media,sys,proc,tmp}/
# create a few folders we excluded, just in case they are needed
mkdir myfs/media myfs/sys myfs/mnt myfs/proc myfs/tmp
#make the squashed filesystem
mksquashfs myfs/ iso/live/filesystem.squashfs
# make the new ISO
mkisofs -r -J -l -D -V "customCD" -o mysystemcd.iso \-cache-inodes -b isolinux/isolinux.bin -c isolinux/boot.cat \-no-emul-boot -boot-load-size 4 -boot-info-table iso/
or like this for more larger iso
mkisofs -r -J -l -D -V "customCD" -o mysystemcd.iso \-cache-inodes -b isolinux/isolinux.bin -c isolinux/boot.cat \-no-emul-boot -allow-limited-size -boot-load-size 4 -boot-info-table iso/
# or you can play even looser with the standards
mkisofs -r -J -l -D -V "customCD" -iso-level 4 -o mysystemcd.iso \-cache-inodes -b isolinux/isolinux.bin -c isolinux/boot.cat \-no-emul-boot -boot-load-size 4 -boot-info-table iso/
#or this if the size is larger
# if you copy/paste the above commands be sure not to have a space after the \
mkisofs -r -J -l -D -V "customCD" -iso-level 4 -o mysystemcd.iso \-cache-inodes -b isolinux/isolinux.bin -c isolinux/boot.cat \-no-emul-boot -allow-limited-size -boot-load-size 4 -boot-info-table iso/
# change ownership of the ISO we created to our user
chown your_user_name:your_user_name mysystemcd.iso
# move the ISO to the desktop
mv mysystemcd.iso /home/your_user_name/Desktop
# move up a directory
cd ..
# delete the work folder
rm -rf work/
# look on the desktop
# mysystemcd.iso is the image of your system
if for some reason you dont have the command mkisofs you must download the programm..( mkisofs alternatives genisoimage)
thk you and good luck!!!
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