Hi All,
I am using Debian Mate and try to make an iso file from my file system after making some modifications (remove unnecessary programs and adding some new). But when I use remastersys to create a distributable iso image, it told me that my filesystem is too large to be an iso file.
I'm wondering what makes it too large (my personal file in the home folder is only about 20MB) and I didn't add too much programs to my system.
When I do some research, I found another filesystem inside my filesystem. It's in the /lib/live/mount/medium directory containing the exactly same files with my USB flash drive that I used to install my system.
Another one is in the /lib/live/mount/rootfs folder, it contains filesystem.squashfs folder. And inside this folder, I found another filesystem too in /lib/live/mount/rootfs/filesystem.squashfs/lib/live/mount/rootfs/filesystem.squashfs.
So there are 4 filesystems in total, perhaps that's why my filesystem is too large to make it an iso image. My question is, are those file really necessary or just useless files that eat up my storage?
I've tried to delete them, reboot my computer, and everything is OK. Then I try to make it an ISO image again using remastersys, completed, then burn it to my flash drive using rufus (as usual). But when I boot my computer from the USB flash drive, after selected the live boot mode, only blank screen with a single X sign appeared on the screen.
Honestly, this is my first trial of making an ISO image from my system. I've got this debian iso from my programmer (and totally sure that he was made his own modification on it).
I want to know those files usage and what was wrong when I used remastersys.
Thank you, All!

some info on file size limits for iso's

https://en.wikipedia.org/wiki/ISO_9660

https://en.wikipedia.org/wiki/ISO_image

http://wiki.osdev.org/ISO_9660

Thanks BW-userx
Then, what should I do to reduce my filesystem size to make it small enough to be an iso (without remove any modifications that I have made, of course)
I have no idea what makes it too big, perhaps the files that I've mentioned above, or another?

1. how to fit a square into a hole without making it the same size needed to work? good question.
2. Only you can answer that last question. I do not have your data to look at.

One creates an OS puts it into an iso file. then has something called a repo to add the rest if needed.
if the things are too many to fit onto one plate, most people get a second plate. Or just cut back on what they are trying to take.

First, my filesystem should be in normal size since I didn't modificate it too much.
Second, my personal data is only about 20MB in size, the rest belong to file system. I have no data which consume big capacity of my storage, then wonder out what is so big inside. What I found had been written in my post above.

you'd have to look into this
Directories and files
and
Directory depth limit
and
The 2/4 GiB file size limit
https://en.wikipedia.org/wiki/ISO_9660

as you stated you have other file systems within and within
"Another one is in the /lib/live/mount/rootfs folder, it contains filesystem.squashfs folder. And inside this folder, I found another filesystem too in /lib/live/mount/rootfs/filesystem.squashfs/lib/live/mount/rootfs/filesystem.squashfs."

It says that the iso file should not be more than 4GB and maximum 8 level of directories. I have some ideas that may could be the solution. I will do some more experiments then post the result here soon.

Thanks a lot BW-userx
I'll be back soon

There are different versions of remastersys for Debian and Ubuntu derivatives. Did you get the correct one?
Remastersys has not actually been in development for some time and may not work at all on newer Debian/Ubuntu installs.
The limit for an iso is 4GB and my experience is that a 9.6GB installed system is compressed to a 3.6GB iso so if your Debian root system is much larger than 10GB, it probably will fail.

Replacements for remastersys which work on some Linux systems are 'PingGuy Builder' and 'Systemback'. If you don't have any luck with remastersys, you might try the other software.

Remastersys creates an iso of the installed system. If you want to include anything in your /home/user directory, you need to use the 'Backup' option. You can check the size of the installed/mounted system with df -h. Unplug or unmount any devices/partitions you don't want on the iso which would include the flash drive you used to install.

My system reaches about 13GB
Someone told me that this is the remastersys minor : your file system will get bigger everytime you back it up to iso (I'll seek out more about it)
I use remastersys which is included in the system, I didn't install it manually
I will try your recommendation about PingGuy Builder and Systemback, too. It will be a good experience to try as many things as possible, especially for a newbie like me.
Thanks yancek!

I'm looking in to that one out of curiosity. That'd be a good thing.

here is something else that is a fork

Welcome to Respin
We are a fork of Remastersys. The remastersys fork - Respin forum will be available soon.

mod: aahhgg debian based arug..

Relinux

how to relinux

I leave it up to one who looks to decide

Good luck with that.

After running remastersys, you will see a remastersys directory in the /home directory. Before running it a second time, you need to remove all those files created. I think there is a 'clean' option within remastersys. Also, if the iso didn't 'work', make sure to delete it before running it again.

It is possible to create iso files larger than 4GB with the multi-extent feature. From the Wikipedia page given previously

https://en.wikipedia.org/wiki/ISO_96...ile_size_limit

There are OS isos much larger than 4GB. Centos 7 has an everything iso that is 7.7 GB. Fedora used to have similar complete iso files over 6-7 GB in size which stopped at Fedora 22. Centos still has these very large isos. You just need to use something other than Remastersys to create them.

The Wikipedia page above mentions the command line mkisofs among other graphical programs. I recommend starting with mkisofs.

Hi All,
I've repeat the steps but it's result's same still.
Finally, I download Debian Jessie 8.8, customize it, then make it an iso. Success!
I'm still not sure what makes my old Debian (Wheezy, 7.2) too big and can't be made an iso.

You could very well make an iso out of Debian (Wheezy, 7.2) no matter how big it was as long as you used something better than Remastersys. As the Wikipedia page mentions other software doesn't have the 4GB limit as they can create multi-extent isos. For example, the free software such as InfraRecorder, ImgBurn and mkisofs as well as Roxio Toast are able to create ISO 9660 filesystems that use multi-extent files to store files larger than 4 GB on appropriate media such as recordable DVDs.

As mentioned Centos 7 currently has a 7.7 GB iso file for download. The largest OS iso file I remember was over 11 GB.

With better software to create iso files you don't have a 4GB limit and so don't need luck or for that matter jerky responses from a "guru".

filesystem.squashfs makes me think you had a live version but not always.

Generally when a distro wants to save space they turn to squash file system. You have to unsquash it and edit then re-squash it back.