What are the essential Startfiles?

[corado]

What are the essential Startfile like DOS, MSDOS.SYS, IOSYS, Command .com, autoexec.bat and config sys?
I mean Linux without X, only the essential files.
Where can I see this? Or get more informations about this?

 

[dos2unix]

In Linux, the essential startup files and configurations are quite different from those in DOS. Here are some key files and directories that play crucial roles in the boot process and system initialization, especially in a system without a graphical interface (X):

1. /boot: This directory contains the kernel and bootloader files. Key files include:
   • vmlinuz: The compressed Linux kernel.
   • initrd.img: The initial ramdisk, which contains necessary drivers and scripts to mount the root filesystem.
2. /etc/fstab: This file contains information about disk partitions and filesystems that should be mounted at boot time.
3. /etc/inittab: Although less common in modern systems using systemd, this file was traditionally used to define runlevels and the initialization process.
4. /etc/init.d/: This directory contains initialization scripts for various services. These scripts are executed during the boot process to start and stop services.
5. /etc/rc.local: This script is executed at the end of the multi-user runlevel. It’s often used for commands that should run at startup.
6. /etc/sysctl.conf: This file is used to configure kernel parameters at runtime.
7. /etc/network/interfaces: On Debian-based systems, this file configures network interfaces.
8. /etc/hostname: This file contains the system’s hostname.
9. /etc/hosts: This file maps hostnames to IP addresses.
10. /etc/resolv.conf: This file contains DNS server information.
11. /etc/passwd and /etc/shadow: These files contain user account information and encrypted passwords, respectively.
12. /etc/profile and ~/.bashrc: These files are used to configure the shell environment for users.

 

[MikeRocor]

What are the essential Startfile like DOS, MSDOS.SYS, IOSYS, Command .com, autoexec.bat and config sys?
I mean Linux without X, only the essential files.
Where can I see this? Or get more informations about this?

I surmise from the way your question is phrased that you are fairly new to linux and that you were hoping for a somewhat simpler answer than the one dos2unix provided. Correct me if I'm wrong on either count. You can pretty much forget the "simpler answer" but perhaps a bit of explanation might help.

While DOS is a single user, single process system, linux is a multitasking, multi user system so there's a whole lot more going on. Multitasking: there are many processes sharing system resources (and the kernel pretty much handles all that on its own, though you're nor entirely without any say in it). Multi user: even if you will always be the only user logged in, your system is designed to be able to accommodate multiple users (possibly many of them and possibly all logged in at the same time).

At a high level the boot process for linux goes something like this (all this in the absence of systemd, with which I have no experience):

• the "boot loader" finds the "kernel" and "initrd image" and
• loads the initrd image into RAM as the "initial ram disk" and
• loads and executes the kernal, passing command line arguments to it

At this point things can go in a bunch of different directions.
The initrd contains a bunch of the files, or perhaps preliminary versions of a bunch of the files, mentioned above by dos2unix.

These files may (usually) tell the kernel where to find the root filesystem (which might be on any partition), in which case the kernel "mounts" the root filesystem, transfers its operations there and then removes the initrd from memory. In this case, the files in the initrd are no longer needed and are no longer (easily) accessible (so good luck finding out what really happened at boot time).

In other cases, the files in the initrd contain everything the kernel needs to operate the system and the initrd itself remains in RAM as the root filesystem.

Either way, once the root file system is known, various config files (usually under /etc/ ) control things like what background processes are started ("services" and "daemons" are pretty much interchangeable terms), what disk based filesystems (if any) will be mounted and on and on - finally ending with either displaying a login prompt on the local console or starting a GUI and displaying a login dialog.

To learn about this stuff, there is no substitute for just installing a simple gui-less linux distro on a USB stick or a spare computer and just mucking with it without fear of breaking anything. The internet as a whole and this forum in particular are incredible resources for additional information as will be the wiki and/or forum for whatever distro you choose.

Somebody please chime in and tell him how badly I've oversimplified this.

 

[f33dm3bits]

@dos2unix You forgot to mention systemd or init system