Basic Google Interview Questions

What are the steps of the Linux Boot Process?

1. BIOS (Power On Self Test), loads MBR
2. MBR - Master Boot Record, loads and executes GRUB boot loader
3. GRUB - GRand Unified Bootloader, loads and executes the kernel and initrd image.
3. Kernel - Mounts the root file system as specified in the "root=" in
4. Init - to determine run level
5. Run Level Programs - Services and programs are loaded depending on the run level

What is the MBR?

* Master Boot Record
* Located in the first sector of the bootable disk (/dev/hda or /dev/sda)
* 512 bytes
* Primary Boot Loader 446 bytes
* Partition Table Info 64 bytes
* MBR validation check 2 bytes
* Contains info about the GRUB
* MBR executes the GRUB boot loader

What are the most common network protocols and ports?

* SSH - Port 22
* Telnet - Port 23
* SMTP - Port 25
* DNS - Port 53
* BOOTP - Port 67
* HTTP - Port 80
* HTTPS - Port 443

What is Apache?

Most commonly used web server software.

What is MySQL ?

Most widely used Open Source data base Server.

What is MONO?

Open Source implementation of .Net for Linux

What is CUPS?

Most commonly used printing server.

What is POSTFIX?

Mail Transfer Agent.

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