chroot which stands for change root allows you to virtually operate in another operating system even though you haven't booted it. It is commonly used to deploy new distros, applications and to fix a broken Linux/Unix install or prep a new system image without having to physically boot the drive or disk.
So in this example let's say we have a drive that has a Linux OS installed on /dev/sdb1 and we have mounted this partition on /mnt/sdb1
The key point is to edit the "chrootdevpath" to match where your intended chroot target is actually mounted to.
After that the bash script below mounts dev, proc and sys into the chroot path so you can interact with all hardware and devices (you can even use this to install grub to sdb).
for mount in dev proc sys; do
mount -o bind /$mount $chrootdevpath/$mount
#now let's chroot into our dev path /dev/sdb1
The above is what I find to be the easiest way of chrooting since you don't have to type any commands aside and you just have to modify one variable and the rest is done for you.
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