GRUB - Rescue BootLoader on a USB Flash Drive

My goal is to just have a GRUB bootloader (without a Linux instalation) on a USB Flash Drive to:

• Boot OS with Bootloaders without entering the BIOS
• Boot OS with Broken Boot Loaders
• Boot Linux Live CDs

 

Installing the GRUB Boot Loader

Run a live CD like Ubuntu, a boot i without installing it.

First list your disks in order to identify you USB Flash Drive

    sudo fdisk -l

if you have trouble identifying you USB Flash Drive just run the command above without the USB Flash Drive, the insert it and list again, compare the outputs, and the extra disk is you USB Flash Drive.

My USB Flash Drive is “sdb1” (b=second HD | 1=first partition), now let’s make a folder to mount the usb flash drive (my Flash Drive was formated with the ext4 filesystem), and mount it:

    sudo mkdir /mnt/USB
    sudo mount /dev/sdb1 /mnt/USB

Now let’s just install the the bootloader

    sudo grub-install --force --removable --boot-directory=/mnt/USB/boot /dev/sdb

boot code goes on /dev/sdb and grub files on /mnt/USB/boot.

 

Set Up the Grub Configuration FIle

Now just create/edit the grub config file

    nano /mnt/USB/boot/grub/grub.cfg

and input the following configuration:

grub.cfg
_____________________________________________

set timeout=10
set default=0

menuentry "#### Boot OS with Bootloaders without entering the BIOS ####" {set root=(hd1)}

menuentry "HD0 (First HD – This USB Flash Drive)" {
set root=(hd0)
chainloader +1
}

menuentry "HD1 (Second HD)" {
set root=(hd1)
chainloader +1
}

menuentry "HD2 (Third HD)" {
set root=(hd2)
chainloader +1
}

menuentry "HD3 (Fourth HD)" {
set root=(hd3)
chainloader +1
}

 

menuentry "#### Boot OS with Broken Boot Loaders ####" {set root=(hd1)}

menuentry "Ubuntu 16.04 (HD1 - First HD)"  {

    insmod part_msdos
    insmod ext2
    set root=(hd1,msdos1)

    echo 'Loading Linux Kernel...'
    linux /boot/vmlinuz-4.4.0-24-generic root=/dev/sda1
       
    echo 'Loading Initial Ramdisk ...'
    initrd /boot/initrd.img-4.4.0-24-generic
    boot
}

menuentry "Windows XP/7/10 (HD1 - First HD)"  {

    insmod part_msdos
    insmod ntfs
    set root=(hd1,msdos1)

    drivemap -s (hd0) ${root}
    chainloader +1
}

 

menuentry "#### Boot Linux Live CDs ####" {set root=(hd1)}
   
menuentry "Ubuntu 16.04 ISO (On This USB PEN Drive)" {

    set isofile="/ubuntu-16.04-desktop-amd64.iso"
    loopback loop (hd0,msdos1)$isofile
    linux (loop)/casper/vmlinuz.efi boot=casper iso-scan/filename=$isofile noprompt noeject
    initrd (loop)/casper/initrd.lz
}

This is what it looks like:

You migth need to adjust some things if you have more disks, partitions or diferent linux distro. To make it easyer I have put the things you migth need to change in bold.

The above config was for the following setup

• One USB Flash Drive (with Grub Installed)
  • hd0,msdos1 - First HD | First Partition – MBR Geometry
  • This is was my USB Flash Drive
• One Hard Drive for OS
  • hd1,msdos1 – Second HD | First Partition – MBR Geometry
  • This is the Disk with the OS

If you have trouble Identifying you disks and partion you can press ‘c’, on the grub menu, to get the GRUB command line and run “ls” :

this was very hepfull, specially identifying the the name for the MBR partitions aka “msdos” .

Related Links

• http://www.pendrivelinux.com/install-grub2-on-usb-from-ubuntu-linux/
• https://www.gnu.org/software/grub/manual/html_node/Chain_002dloading.html
• http://ubuntuhandbook.org/index.php/2014/04/install-grub-customizer-ubuntu-1404/

Linux – Howto Boot an ISO from GRUB

Linux’s GRUB2 boot loader can boot Linux ISO files directly from your hard drive. Boot Linux live CDs or even install Linux on another hard drive partition without burning it to disc or booting from a USB drive.

We performed this process on Ubuntu 14.04 — Ubuntu and Ubuntu-based Linux distributions have good support for this. Other Linux distributions should work similarly.

This trick requires you have a Linux system installed on your hard drive. Your computer must be using the GRUB2 boot loader, which is a standard boot loader on most Linux systems. Sorry, you can’t boot a Linux ISO file directly from a Windows system using the Windows boot loader.

Download the ISO files you want to use and store them on your Linux partition. GRUB2 should support most Linux systems. if you want to use them in a live environment without installing them to your hard drive, be sure to download the “live CD” versions of each Linux ISO. Many Linux-based bootable utility discs should also work.

 

Check the Contents of the ISO File

You may need to look inside the ISO file to determine exactly where specific files are. For example, you can do this by opening the ISO file with the Archive Manager/File Roller graphical application that comes with Ubuntu and other GNOME-based desktop environments. In the Nautilus file manager, right-click the ISO file and select Open with Archive Manager.

Locate the kernel file and the initrd image. If you’re using a Ubuntu ISO file, you’ll find these files inside the casper folder — the vmlinuz file is the Linux kernel and the initrd file is the initrd image. You’ll need to know their location inside the ISO file later.

 

Determine the Hard Drive Partition’s Path

GRUB uses a different “device name” scheme than Linux does. On a Linux system, /dev/sda1 is the first partition on the first hard disk — a means the first hard disk and 1 means its first partition. In GRUB, (hd0,1) is equivalent to /dev/sda0. The 0 means the first hard disk, while the1 means the first partition on it. In other words, in a GRUB device name, the disk numbers start counting at 0 and the partition num6ers start counting at 1 — yes, it’s unnecessarily confusing. For example, (hd3,6) refers to the sixth partition on the fourth hard disk.

You can use the fdisk -l command to view this information. On Ubuntu, open a Terminal and run the following command:

sudo fdisk -l

You’ll see a list of Linux device paths, which you can convert to GRUB device names on your own. For example, below we can see the system partition is /dev/sda1 — so that’s (hd0,1) for GRUB.

 

Create the GRUB2 Boot Entry

The easiest way to add a custom boot entry is to edit the /etc/grub.d/40_custom script. This file is designed for user-added custom boot entries. After editing the file, the contents of your /etc/defaults/grub file and the /etc/grub.d/ scripts will be combined to create a /boot/grub/grub.cfg file — you shouldn’t edit this file by hand. It’s designed to be automatically generated from settings you specify in other files.

You’ll need to open the /etc/grub.d/40_custom file for editing with root privileges. On Ubuntu, you can do this by opening a Terminal window and running the following command:

sudo gedit /etc/grub.d/40_custom

Feel free to open the file in your favorite text editor. For example, you could replace “gedit” with “nano” in the command to open the file in the Nano text editor.

Unless you’ve added other custom boot entries, you should see a mostly empty file. You’ll need to add one or more ISO-booting sections to the file below the commented lines.

Here’s how you can boot an Ubuntu or Ubuntu-based distribution from an ISO file. We tested this with Ubuntu 14.04:

menuentry “Ubuntu 14.04 ISO” {
set isofile=”/home/name/Downloads/ubuntu-14.04.1-desktop-amd64.iso”
loopback loop (hd0,1)$isofile
linux (loop)/casper/vmlinuz.efi boot=casper iso-scan/filename=${isofile} quiet splash
initrd (loop)/casper/initrd.lz
}

Customize the boot entry to contain your desiredmenu entry name, the correct path to the ISO file on your computer, and the device name of the hard disk and partition containing the ISO file. If the vmlinuz and initrd files have different names or paths, be sure to specify the correct path to those files, too.

(If you have a separate /home/ partition, omit the /home bit, like so: set isofile=”/name/Downloads/${isoname}”).

Important Note: Different Linux distributions require different boot entries with different boot options. The GRUB Live ISO Multiboot project offers a variety of menu entries for different Linux distributions. You should be able to adapt these example menu entries for the ISO file you want to boot. You can also just perform a web search for the name and release number of the Linux distribution you want to boot along with “boot from ISO in GRUB” to find more information.

If you want to add more ISO boot options, add additional sections to the file.

Save the file when you’re done. Return to a Terminal window and run the following command:

sudo update-grub

The next time you boot your computer, you’ll see the ISO boot entry and you can choose it to boot the ISO file. You may have to hold Shift while booting to see the GRUB menu.

If you see an error message or a black screen when you attempt to boot the ISO file, you misconfigured the boot entry somehow. Even if you got the ISO file path and device name right, the paths to the vmlinuz and intird files on the ISO file may not be correct or the Linux system you’re booting may require different options.

Taken From: http://www.howtogeek.com/196933/how-to-boot-linux-iso-images-directly-from-your-hard-drive/

Windows 8 and The New UEFI BIOS

How To Access The BIOS On A Windows 8 Computer

Among the many changes coming with Windows 8 and new computers designed for it is a change in the way we access our computers’ BIOS. No longer do we press a certain key during the boot process to reveal the BIOS – instead, an option to access the BIOS is located in Windows 8’s boot options menu.

Traditionally, computers displayed a message like “Press F2 to enter setup” at the beginning of the boot process. Pressing this key entered the computer’s BIOS. However, Windows 8 hardware uses the UEFI replacement for the traditional BIOS, like Macs do. Some solid-state drive-equipped Windows 8 PCs boot so fast that you’d only have a 200 millisecond (that’s 0.2 seconds) window of opportunity to press the key combination.

 

Windows 8 Hardware vs. Old Computers With Windows 8

Note that this new method only applies if you purchased a new computer with Windows 8 preinstalled – these will use UEFI. However, if you’ve installed Windows 8 on an existing computer that uses the legacy BIOS system, you’ll access the BIOS in the same way as always by pressing the key that appears during your boot process.

This key is often F2 or Delete, but it can also be other keys. The exact key depends on your computer – if you don’t see the appropriate key displayed on your screen during the boot-up process, consult your computer’s manual.

 

Accessing Boot Options

There are several ways to access Windows 8’s boot options menu. The easiest one to find is in the PC Settings application – press WinKey+C to reveal the Charms bar, click Settings, and select Change PC settings to access it.

In the PC Settings application, select the General category and click the Restart now button under Advanced startup. Your computer will restart and you’ll enter the Windows 8s boot options menu, where you can access the UEFI BIOS and change other settings.

In more updated versions of windows 8 (like 8.1), the Advanced startup has moved:

Windows Key+C > Settings > Change PC settings > Update and recovery > Recovery > Advanced startup + Restart now

You can also hold Shift while clicking Restart in the Shut Down menu to restart your computer into the boot options menu. This is a quick way to restart into the boot options menu, as you can access the Shut Down button from the Charms anywhere on your system.

Command-line geeks will be happy to know they can run a special shutdown.exe command in a Command Prompt window to restart their computer directly into the boot options menu:

Shutdown.exe /r /o

 

Accessing UEFI BIOS

The boot options menu has been designed to integrate some commonly used options that people went into the BIOS for. For example, if you want to boot your computer off a USB drive, DVD or CD, or another device, you can click the Use a device tile in the boot options menu and select the device you want to boot from.

If you’re just here to access your computer’s UEFI BIOS, click the Troubleshoot tile.

This will reveal an Advanced Options screen with a variety of tools – the UEFI Firmware Settings tile will take you to your computer’s BIOS. (On UEFI, which stands for “Unified Extensible Firmware Interface”, the firmware settings menu is equivalent to a traditional PC’s BIOS.)

If you don’t see the UEFI Firmware Settings tile here, your computer doesn’t use UEFI. You’ll need to access the BIOS in the traditional way, by pressing a specific key during the boot-up process. See the first section above for more information.

If there’s an error booting Windows, you won’t be locked out of the BIOS — the boot options screen will appear when you start your computer. From here, you can repair Windows or enter your BIOS.

 

Why the Change?

While this may be slightly inconvenient, as there’s no way to access the BIOS in normal use without booting into Windows first, it’s surely necessary. Microsoft’s blog post about this on the Building Windows 8 blog describes how this new system came to be. With the increased boot speed, some systems had a less than 200 millisecond window of opportunity to press a key. Even the best key-tappers at Microsoft could only press a key once every 250ms — to access the BIOS, frantic tapping, luck, and several compuer reboots were all necessary.

This also brings some much-needed consistency to Windows 8 computers — they’ll all have a consistent way of accessing the BIOS. Currently, different computers use different keys at start-up.

While Windows 8 may have some questionable design decisions that some people will dislike, this shouldn’t be one of them. The new method of accessing the BIOS is necessary and well-implemented.

Taken From: http://www.makeuseof.com/tag/how-to-access-the-bios-on-a-windows-8-computer/ (By Chris Hoffman)

How to Create Bootable USB Drives and SD Cards For Every Operating System

How to Create Bootable USB Drives and SD Cards For Every Operating System

Creating installation media for your operating system of choice used to be simple. Just download an ISO and burn it to CD or DVD. Now we’re using USB drives, and the process is a little different for each operating system.

You can’t just copy files form an ISO disc image directly onto your USB drive. The USB drive’s data partition needs to be made bootable, for one thing. This process will usually wipe your USB drive or SD card.

From a Linux ISO

Ubuntu recommends the Universal USB Installer for creating bootable Linux USB drives on Windows. This tool can create bootable disc images for many different Linux distributions.UNetbootin is another popular alternative.

Download the Linux distribution you want to use in .ISO form. Run the tool, select your desired distribution, browse to your downloaded ISO file, and choose the USB drive you want to use. The tool will do the rest.

You can use similar tools on Linux. For example, Ubuntu includes a Startup Disk Creator tool for creating bootable Ubuntu USB drives. UNetbootin also runs on Linux, so you can use that too.

From an IMG File

Some operating system projects provide an IMG file instead of an ISO file. An IMG file is a raw disk image that needs to be written directly to a USB drive.

Use Win32 Disk Imager to write an IMG file to a USB drive or SD card. Provide a downloaded IMG file and the tool will write it directly to your drive, erasing its current contents. You can also use this tool to create IMG files from USB drives and SD cards.

Linux users can use the dd command to directly write an IMG file’s contents to a removable media device. Insert the removable media and run the following command on Ubuntu:

sudo dd if=/home/user/file.img of=/dev/sdX bs=1M

Replace /home/user/file.img with the path to the IMG file on your file system and /dev/sdX with the path to your USB or SD card device. Be very careful to specify the correct disk path here — if you specify the path to your system drive instead, you’ll write the contents of the image to your operating system drive and corrupt it

From a Windows 7 ISO

Provide the ISO file and a USB flash drive and the tool will create a bootable drive.

From a Windows 8 or 8.1 Product Key

If you have a Windows 8 or Windows 8.1 product key, you can download installation media directly from Microsoft and create a USB drive all at once. Download the appropriate tool from the Upgrade Windows with only a product key page. Run it, provide your product key, and tell the wizard you want to create a bootable USB drive.

Note that Windows 8 and Windows 8.1 have different product keys, so you’ll need to jump through hoops if you want to install Windows 8.1 with a Windows 8 product key. You may just want to install Windows 8 and upgrade to Windows 8.1 from within Windows 8 — that’s Microsoft’s officially supported method.

From a Windows 8 or 8.1 ISO

If you already have a Windows 8 or 8.1 ISO file and you want to create installation media without redownloading anything, you can actually use the Windows 7 USB/DVD download tool for this.

Just provide the Windows 8 or 8.1 ISO file when prompted. The tool will happily create Windows 8 or 8.1 installation media if you provide the appropriate ISO file.

If you need to boot into DOS to use a low-level firmware upgrade, BIOS update, or system tool that still requires DOS for some reason, you can use the Rufus tool to create a bootable DOS USB drive.

Rufus uses FreeDOS, an open-source implementation of DOS that should run whatever DOS program you need to use.

From Mac OS X Installation Files

You can create a bootable drive with Mac OS X on it by downloading the latest version of OS X from the Mac App Store. Use Apple’s included “createinstallmedia” tool in a terminal or by run the third-party DiskMaker X tool.

The Mac OS X drive can be used to install OS X on other Macs or upgrade them to the latest version without any long downloads.

From a Windows ISO for Mac

If you plan on installing Windows on a Mac via Boot Camp, don’t bother creating a bootable USB drive in the usual way. Use your Mac’s Boot Camp tool to start setting things up and it will walk you through creating a bootable Windows installation drive with Apple’s drivers and Boot Camp utilities integrated.

You can use this drive to install Windows on multiple Macs, but don’t use it to install Windows on non-Apple PCs.

Some of these tools overlap — for example, Rufus can also be used to create bootable drives from Linux ISOs, IMG files, and even Windows ISO Files. We suggested the most popular, widely recommended tools for each task here.

Image Credit: USBMemoryDirect on Flickr

Taken From: http://www.howtogeek.com/191054/how-to-create-bootable-usb-drives-and-sd-cards-for-every-operating-system/

Boot Linux ISOs From Hard Drive ( GRUB )

How to Boot Linux ISO Images Directly From Your Hard Drive

Linux’s GRUB2 boot loader can boot Linux ISO files directly from your hard drive. Boot Linux live CDs or even install Linux on another hard drive partition without burning it to disc or booting from a USB drive.

We performed this process on Ubuntu 14.04 — Ubuntu and Ubuntu-based Linux distributions have good support for this. Other Linux distributions should work similarly.

Get a Linux ISO File

How to Configure the GRUB2 Boot Loader’s Settings
Ubuntu and most other Linux distributions now use the GRUB2 boot loader. You can change its settings to select a... [Read Article]

This trick requires you have a Linux system installed on your hard drive. Your computer must be using the GRUB2 boot loader, which is a standard boot loader on most Linux systems. Sorry, you can’t boot a Linux ISO file directly from a Windows system using the Windows boot loader.

Download the ISO files you want to use and store them on your Linux partition. GRUB2 should support most Linux systems. if you want to use them in a live environment without installing them to your hard drive, be sure to download the “live CD” versions of each Linux ISO. Many Linux-based bootable utility discs should also work.

Check the Contents of the ISO File

You may need to look inside the ISO file to determine exactly where specific files are. For example, you can do this by opening the ISO file with the Archive Manager/File Roller graphical application that comes with Ubuntu and other GNOME-based desktop environments. In the Nautilus file manager, right-click the ISO file and select Open with Archive Manager.

Locate the kernel file and the initrd image. If you’re using a Ubuntu ISO file, you’ll find these files inside the casper folder — the vmlinuz file is the Linux kernel and the initrd file is the initrd image. You’ll need to know their location inside the ISO file later.

Determine the Hard Drive Partition’s Path

GRUB uses a different “device name” scheme than Linux does. On a Linux system, /dev/sda0 is the first partition on the first hard disk — a means the first hard disk and 0 means its first partition. In GRUB, (hd0,1) is equivalent to /dev/sda0. The 0 means the first hard disk, while the1 means the first partition on it. In other words, in a GRUB device name, the disk numbers start counting at 0 and the partition num6ers start counting at 1 — yes, it’s unnecessarily confusing. For example, (hd3,6) refers to the sixth partition on the fourth hard disk.

You can use the fdisk -l command to view this information. On Ubuntu, open a Terminal and run the following command:

sudo fdisk -l

You’ll see a list of Linux device paths, which you can convert to GRUB device names on your own. For example, below we can see the system partition is /dev/sda1 — so that’s (hd0,1) for GRUB.

Create the GRUB2 Boot Entry

The easiest way to add a custom boot entry is to edit the /etc/grub.d/40_custom script. This file is designed for user-added custom boot entries. After editing the file, the contents of your /etc/defaults/grub file and the /etc/grub.d/ scripts will be combined to create a /boot/grub/grub.cfg file — you shouldn’t edit this file by hand. It’s designed to be automatically generated from settings you specify in other files.

You’ll need to open the /etc/grub.d/40_custom file for editing with root privileges. On Ubuntu, you can do this by opening a Terminal window and running the following command:

sudo gedit /etc/grub.d/40_custom

Feel free to open the file in your favorite text editor. For example, you could replace “gedit” with “nano” in the command to open the file in the Nano text editor.

Unless you’ve added other custom boot entries, you should see a mostly empty file. You’ll need to add one or more ISO-booting sections to the file below the commented lines.

Here’s how you can boot an Ubuntu or Ubuntu-based distribution from an ISO file. We tested this with Ubuntu 14.04:

menuentry “Ubuntu 14.04 ISO” {
set isofile=”/home/name/Downloads/ubuntu-14.04.1-desktop-amd64.iso”
loopback loop (hd0,1)$isofile
linux (loop)/casper/vmlinuz.efi boot=casper iso-scan/filename=${isofile} quiet splash
initrd (loop)/casper/initrd.lz
}

Customize the boot entry to contain your desiredmenu entry name, the correct path to the ISO file on your computer, and the device name of the hard disk and partition containing the ISO file. If the vmlinuz and initrd files have different names or paths, be sure to specify the correct path to those files, too.

(If you have a separate /home/ partition, omit the /home bit, like so: set isofile=”/name/Downloads/${isoname}”).

Important Note: Different Linux distributions require different boot entries with different boot options. The GRUB Live ISO Multiboot project offers a variety of menu entries for different Linux distributions. You should be able to adapt these example menu entries for the ISO file you want to boot. You can also just perform a web search for the name and release number of the Linux distribution you want to boot along with “boot from ISO in GRUB” to find more information.

If you want to add more ISO boot options, add additional sections to the file.

Save the file when you’re done. Return to a Terminal window and run the following command:

sudo update-grub

The next time you boot your computer, you’ll see the ISO boot entry and you can choose it to boot the ISO file. You may have to hold Shift while booting to see the GRUB menu.

If you see an error message or a black screen when you attempt to boot the ISO file, you misconfigured the boot entry somehow. Even if you got the ISO file path and device name right, the paths to the vmlinuz and intird files on the ISO file may not be correct or the Linux system you’re booting may require different options.

Taken From: http://www.howtogeek.com/196933/how-to-boot-linux-iso-images-directly-from-your-hard-drive/

Linux – Start / Stop Services (Boot + Runlevel)

How-To: Managing services with update-rc.d

Linux services can be started, stopped and reloaded with the use of scripts stocked in /etc/init.d/.

However, during start up or when changing runlevel, those scripts are searched in /etc/rcX.d/ where X is the runlevel number.

This tutorial will explain how one can activate, deactivate or modify a service start up.

When installing a new service under debian, the default is to enable it. So for instance, if you just installed apache2package, after you installed it, apache service will be started and so will it be upon the next reboots.

If you do not use apache all the time, you might want to disable this service from starting up upon boot up and simply start it manually when you actually need it by running this command:

# /etc/init.d/apache2 start

As you can see in the output below, the scripts are in init.d but the boot process executes the scripts on rcX.d (X is the runlevel), so we have symbolic links in rcX.d that point to the scripts on init.d. For something, not to be exectuted at boot, we have to destroy the symbolic links at rcX.d, this can either be done manually or via the update-rc.d  

You could either disable this service on boot up by removing manually, any symbolic links in /etc/rcX.d/SYYapache2 or by using update-rc.d.

The advantage of using update-rc.d is that it will take care of removing/adding any required links to /etc/init.d automatically.
Taking apache2 as an example, let’s examine how /etc/rcX.d is looking like:

# ls -l /etc/rc?.d/*apache2
lrwxrwxrwx 1 root root 17 2007-07-05 22:51 /etc/rc0.d/K91apache2 -> ../init.d/apache2
lrwxrwxrwx 1 root root 17 2007-07-05 22:51 /etc/rc1.d/K91apache2 -> ../init.d/apache2
lrwxrwxrwx 1 root root 17 2007-07-05 22:51 /etc/rc2.d/S91apache2 -> ../init.d/apache2
lrwxrwxrwx 1 root root 17 2007-07-05 22:51 /etc/rc3.d/S91apache2 -> ../init.d/apache2
lrwxrwxrwx 1 root root 17 2007-07-05 22:51 /etc/rc4.d/S91apache2 -> ../init.d/apache2
lrwxrwxrwx 1 root root 17 2007-07-05 22:51 /etc/rc5.d/S91apache2 -> ../init.d/apache2
lrwxrwxrwx 1 root root 17 2007-07-05 22:51 /etc/rc6.d/K91apache2 -> ../init.d/apache2

As you can see, for runlevels 0, 1 and 6 there is a K (aka Kill) at the beginning of the link, for runlevels 2, 3, 4 and 5, there is a S (aka Start). Those two letters stands for Kill and Start.
On Debian and Ubuntu, runlevels 2, 3, 4 and 5 are multi-users runlevels.

- Runlevel 0 is Halt.
- Runlevel 1 is single user mode
- Runlevel 6 is reboot

1. Removing a Service

If you want to totally disable apache2 service by hand, you would need to delete every single link in /etc/rcX.d/. Using update-rc.d it is as simple as:

# update-rc.d -f apache2 remove

The use of -f is to force the removal of the symlinks even if there is still /etc/init.d/apache2.

Note: This command will only disable the service until next time the service is upgraded. If you want to make sure the service won’t be re-enabled upon upgrade, you should also type the following:

# update-rc.d apache2 stop 80 0 1 2 3 4 5 6 .

2. Adding a service

2.1. Default priorities

Now, if you want to re-add (enable) this service to be started on boot up, you can simply use:

# update-rc.d apache2 defaults

Adding system startup for /etc/init.d/apache2 …
/etc/rc0.d/K20apache2 -> ../init.d/apache2
/etc/rc1.d/K20apache2 -> ../init.d/apache2
/etc/rc6.d/K20apache2 -> ../init.d/apache2
/etc/rc2.d/S20apache2 -> ../init.d/apache2
/etc/rc3.d/S20apache2 -> ../init.d/apache2
/etc/rc4.d/S20apache2 -> ../init.d/apache2
/etc/rc5.d/S20apache2 -> ../init.d/apache2

2.2. Custom priorities

But as you can see, the default value is 20 which is pretty different than 91 … a S20 link is started before a S91 and K91 is kill before K20.
To force apache2 to be started with priorities 91 for both Start and Kill, we need to use the following command:

# update-rc.d apache2 defaults 91

Adding system startup for /etc/init.d/apache2 …
/etc/rc0.d/K91apache2 -> ../init.d/apache2
/etc/rc1.d/K91apache2 -> ../init.d/apache2
/etc/rc6.d/K91apache2 -> ../init.d/apache2
/etc/rc2.d/S91apache2 -> ../init.d/apache2
/etc/rc3.d/S91apache2 -> ../init.d/apache2
/etc/rc4.d/S91apache2 -> ../init.d/apache2
/etc/rc5.d/S91apache2 -> ../init.d/apache2

2.3. Different priorities for Start and Kill

Alternatively, if you want to set different priorities for Start and Kill, let say Start with 20 and Kill with 80, you will need to run:

# update-rc.d apache2 defaults 20 80

Adding system startup for /etc/init.d/apache2 …
/etc/rc0.d/K80apache2 -> ../init.d/apache2
/etc/rc1.d/K80apache2 -> ../init.d/apache2
/etc/rc6.d/K80apache2 -> ../init.d/apache2
/etc/rc2.d/S20apache2 -> ../init.d/apache2
/etc/rc3.d/S20apache2 -> ../init.d/apache2
/etc/rc4.d/S20apache2 -> ../init.d/apache2
/etc/rc5.d/S20apache2 -> ../init.d/apache2

3. Specifying custom runlevels

Finally, if you only want to Start and Kill on specific runlevels, like for instance starting apache with priority 20 on runlevels 2, 3, 4 and 5 and Kill with priority 80 on runlevels 0, 1 and 6:

# update-rc.d apache2 start 20 2 3 4 5 . stop 80 0 1 6 .

Adding system startup for /etc/init.d/apache2 …
/etc/rc0.d/K80apache2 -> ../init.d/apache2
/etc/rc1.d/K80apache2 -> ../init.d/apache2
/etc/rc6.d/K80apache2 -> ../init.d/apache2
/etc/rc2.d/S20apache2 -> ../init.d/apache2
/etc/rc3.d/S20apache2 -> ../init.d/apache2
/etc/rc4.d/S20apache2 -> ../init.d/apache2
/etc/rc5.d/S20apache2 -> ../init.d/apache2

Or, to start with priority 20 for runlevel 2, 3 and 4 and priority 30 for runlevel 5 and kill with priority 80 for runlevel 0, 1 and 6:

# update-rc.d apache2 start 20 2 3 4 . start 30 5 . stop 80 0 1 6 .

Adding system startup for /etc/init.d/apache2 …
/etc/rc0.d/K80apache2 -> ../init.d/apache2
/etc/rc1.d/K80apache2 -> ../init.d/apache2
/etc/rc6.d/K80apache2 -> ../init.d/apache2
/etc/rc2.d/S20apache2 -> ../init.d/apache2
/etc/rc3.d/S20apache2 -> ../init.d/apache2
/etc/rc4.d/S20apache2 -> ../init.d/apache2
/etc/rc5.d/S30apache2 -> ../init.d/apache2

Based On: http://www.debuntu.org/how-to-managing-services-with-update-rc-d/

Make a Cisco Unified Communication Manager Bootable ISO

How to make Cisco Unified Communication Manager bootable ISO from non-bootable image on Linux

NOVEMBER 18, 2013

Here are the exact steps that help you to make bootable CUCM ISO image from non-bootable ISO image on Linux. If you want to do the same on Windows I strongly recommend to read this tutorial. I could not write my tutorial without reading it first.

Introduction
Typically, non-bootable CUCM images are those available for download on Cisco website. I used Linux Fedora 17 and mkisofs to create bootable CUCM ISO image but feel free to use any Linux distro with genisoimage installed. On Fedora you have to install a package genisoimage to get mkisofs installed.

Used software
Linux Fedora 17 x86-64 with installed genisoimage utility
CUCM 9.1.2 - UCSInstall_UCOS_9.1.2.10000-28.sgn.iso

1. Install genisomage

$ sudo yum install genisomage

Create directory where non-bootable CUCM ISO image will be mounted.

$ mkdir -p ~/temp/extract

2. Create directory where the content of mounted non-bootable ISO image will be copied

$ mkdir -p ~/temp2/

3. Mount non-bootable DVD ISO image

$ sudo mount -t iso9660 ~/Downloads/UCSInstall_UCOS_9.1.2.10000-28.sgn.iso ~/temp/extract

4. Copy the content of mounted ISO image to directory ~/temp2

$ cp -rv ~/temp/extract/ ~/temp2

5.  Create bootable ISO image

cd ~/temp2/extract

mkisofs -o ../UCSInstall_UCOS_9.1.2.10000-28.sgn-bootable.iso -R -no-emul-boot -boot-load-size 32 -boot-info-table -b isolinux/isolinux.bin .

End.

Reference
http://htluo.blogspot.co.uk/2010/04/how-to-make-non-bootable-iso-image.html
http://www.ipcommute.co.uk/technical-articles/17–creating-isolinux-boot-dvds-with-free-software-cucm-uccx-cups.html

 

Taken From: http://brezular.wordpress.com/2013/11/18/how-to-make-cisco-unified-communication-manager-bootable-iso-from-non-bootable-image-on-linux/

Windows 8 Portable USB Drive (No Extra Tools)

For a long time Linux users have been able to install their OS onto a portable USB drive, but Windows just caught up. Read on to find out how you can install Windows 8 onto a USB drive so you can take it wherever you go.

Note: This was written on the RTM version of Windows 8 Enterprise and you will need to have an RTM build of the Enterprise edition to complete the steps in this article.

Using Windows To Go to Create a Portable Workspace

Press the Win + X keyboard combination and select Control Panel from the context menu.

You will need to change your Control Panel view to the Small Icons view.

You should now see Windows To Go near the bottom of the Control Panel, click on it.

You will now need to select the USB drive you would like to turn into a portable workspace, then click next.

The wizard will automatically scan your CD\DVD and Removable drives for valid Windows installation files, once you have selected a version of Windows click next.

Note: If you store your installation files elsewhere you will need to add it as a search location.

You can optionally set a BitLocker password, but we’ll pass on this option for now.

Once you have reached the end of the wizard, you will be warned that your USB drive will be formatted. You can then click on create to kick of the creation process.

That’s all there is to it, you now have a bootable USB with Windows on it.

Note: Your portable USB will not show up in Explorer, this leaves us with a problem later on when you don’t need to use it as a Portable Workspace anymore.

How To Reformat Your Windows To Go USB Drive

If you’re done using Windows on a drive, you can reformat the drive, but you’ll need to open a command prompt and type diskpart, then press enter.

Once you enter Diskpart you will need to find out which drive is the one you need to format, the list disk command will show you all the drive currently connected to your system. Take note of your drive number because we will need it in the next step.

We now need to select the disk, you can simply use the select disk command along with your drive number from the previous step.

Now that the disk is selected we can go ahead and wipe it.

Note: Clean is a ruthless command that will wipe all the file systems off your drive without any warnings, if you have selected the wrong drive previously this will result is a loss of data so make sure you have the right drive selected.

We can now use the Win + R keyboard combination to bring up the run box  and open Disk Management.

As soon as the Management console opens you will need to initialize the disk.

Then you can go ahead and create your drives partition.

That’s all there is to it.

Taken From: http://www.howtogeek.com/121322/how-to-create-a-portable-version-of-windows-8-without-extra-software/

Plop – Boot USB Disks on Old Hardware and VMware

Using Plop Boot Manager for USB Boot

For PLOP USB Disks Booting on VMWARE check this post: http://myhowtosandprojects.blogspot.com/2011/12/boot-from-usb-disk-in-vmware.html

Portability is a huge advantage that Linux enjoys over most other desktop operating systems as most major distros work very well when installed to a flash drive. However, there are still machines in service that just won't play ball when it comes to USB booting. Fortunately, I found a nice little utility that can work around this problem.

Carrying data around on a flash drive is handy, but with Linux, it's possible to carry around an entire work environment. Unfortunately, however, there are some older systems that won't boot from USB. For example, I have a Sempron 3000+ system with 2GB of RAM that won't boot from USB, even though it's a usable system for some things. If the BIOS doesn't support booting from a flash drive, there's not much that GRUB can do as it doesn't contain any drivers and relies on the BIOS to find bootable media.

Plop Boot Manager aims to overcome these limitations. Like most boot managers, it presents a selection menu to choose the boot partition when the machine first starts up. As it contains its own USB drivers, you can use it to convince older hardware to boot from a device such as a flash drive. It's a quite a flexible piece of software. For example, you can set it up to be loaded by GRUB or the Windows boot loader menu or even something more exotic such as loading Plop from from a floppy disk drive in order to initiate a network boot. In this example, I'll just be documenting one single use case in which I used it to enable an older machine to boot from a USB drive.

Standard disclaimer: If you're carrying out a job like this, a single mistake or one bug in the software can easily wipe the contents of the entire disk. Back up valuable data.

In this case, I installed it to the MBR (Master Boot Record) as this is the simplest option. A word of warning here: when installed to the MBR, it will overwrite an existing GRUB installation if it too was placed in the MBR. As Plop isn't a Linux loader, this means that Linux will no longer work. In other words, you will have to reinstall GRUB onto the Linux boot partition itself, if you don't already have it working like that. There might be a slight problem here as USB keyboards wont work until the operating system itself has booted. This means that you can't actually select anything from the Grub menu if you are using a USB keyboard, which should’t be a huge problem for most uses. Obviously, Plop Boot Manager can select between operating systems. An existing Windows installation should continue to work without modification.

Within the archive, there are a few directories with the files needed for different types of installation. In this case I took the ISO installer image (all 480k of it) and burnt it to a CDR. As I said, if this isn't an option with the machine that you're working with, you can install from within an operating system that is already running on the computer. As with all of the system, the installer uses a flashy mixture of text mode and graphics. It's a simple system and it installs very quickly.

Rebooting, you're presented with the installer itself with options for booting from different types of media. As hoped, this allowed me to boot Xubuntu from the USB flash drive. One limitation of the program is that it can't handle booting from USB DVD/CDROM drives which is a shame. It's an interactive boot manager and you can reconfigure it on the fly to change things like appearance and default boot options.

Plop Boot Manager is a versatile piece of software. Risking the ire of Linux graybeards by saying it, I've often wished that more Linux distros made use of something a bit friendlier than the perennial GRUB. If you work with a lot of older hardware and would like to boot from a memory stick, the the ISO version of the boot loader on a CDR might be worth adding to your bag of tricks.

I've only scratched the surface of what Plop can do. Hit the docs for a full feature list.

______________________

UK based freelance writer Michael Reed writes about technology, retro computing, geek culture and gender politics.

Taken From: http://www.linuxjournal.com/content/using-plop-boot-manager-usb-boot