can I make a bootable ISO from my hard disk?
 

Can I make a bootable ISO image from my hard disk? I understand dd does not convert the filesystem, and I have no idea if/how I should update a bootloader. I would like to take my user environment with me on other PC's without them being editable/changeable. Can this be done? How?

have a look at respin(formerly remastersys) and G4L.

Personally, I use dd to make (non-bootable)ISOs. Then boot the target system with a live USB, mount the ISO and copy over.

There are various methods with different Linux systems. Remastersys did this with the Ubuntu derivatives and there is similar software such as Systemback and PinGuyBuilder for the Ubuntu derivatives. Other Linux systems have similar software so knowing which Linux you are using would be needed. These programs would create a bootable iso without the need for the user to add a bootloader. There are limitations on the size of the iso with some of this software.

I'm not sure why it needs to be an ISO file.

It can just be a binary copy of your hard disk, which you would use dd to do this. And if you have a transportable media which is large enough to contain the entire space of your hard disk, then you can use dd to make a copy of that image.

I might be tempted to look at the ways they make live usb's. Basically they take a running system and usually compress most or all of it no a squashfs file (or other compression) and then add some stuff to make it bootable/usable.

It's not easy to modify a squashfs while mounted.

Iso is easy to handle, perhaps that's why he want to make an ISO of it.

Several distros have remastering tools as standard that do exactly what you are looking for.

(Both distros that I use - AntiX & MX Linux).

Thanks for the helpful advise, especially Honest Abe.
Found a few that I will need to test out :
linux-live.org
linuxrespin.org
systemback
remastersys.org (Honest Abe)
livemagic

Slowly climbing the everest of linux ... if anyone has a foolproof guide, plz share!

For future visitors to this thread looking for a command line solution for disk backups, I use the following to take dd backups (non-bootable ISO) -

Note: I run this from Runlevel 1 (rescue.target for systemd users) to minimize IO overhead, though I suppose the same command can also be used from Runlevel 3/5 (multi-user.target & graphical.target respectively for systemd) if you have booted from a live media.

I assumed that the user wanted to create a live optical image and not just a copy of a drive. Could be wrong.

https://www.wikihow.com/Create-an-ISO-File-in-Linux

Is that what you want to do?