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The native partition type code used by a Linux hard drive is 0x83 irrespective of the file system (ext2, ext3, reiserfs etc.). When you partition your hard drive using fdisk or any other utility, it often consists of two partitions: a root directory partition (denoted as '/') and a swap partition. A partition table is the index table that references all Linux hard drive partitions. So, if this table gets corrupt, the system couldn't locate and thus access the partitions. In such situations, you need to use your recent data backup and restore lost information from it. However, if data backup is non-existent, invalid or not updated, Linux Data Recovery tools can be used to scan the affected hard drive.Consider a scenario, you start your Linux system and it displays the following error message:"The partition table on device was unreadable"CauseThe partition table is corrupted or damaged. It can get corrupt due to unexpected shutdown, incorrect installation of updates, improp er use of terminal commands, erroneous use of disk partitioning utilities, partition resizing and other similar causes.SolutionTo correct this issue, you need to carry out these steps:You need to ensure that at least one of the partitions has been marked as ActiveIf you can boot the operating system, you should immediately backup all the important dataNext, you need to delete all the existing partitions and then recreate them. To accomplish the same, you can use fdisk or any other disk partitioning utilityRepartitioning the hard disk erases all the previously stored data. So, you need to use your recent data backup to restore it. If the data backup is not present or up to the mark, you need to scan your hard drive usingLinux Recovery tools to extract the lost data.Linux Data Recovery applications incorporate advanced scanning procedures to recover and restore the lost data. With elf-explanatory interface, these utilities provide easy recovery. In addition, these recovery sof tware are read-only tools and hence they don't perform any write operation. You can use these tools in any logical data loss case. Stellar Phoenix Linux Data Recovery is efficient Linux Recovery tool. The software supports advanced recovery features and provides effective recovery results. It is a read-only tool that supports Ext2, Ext3 and ReiserFS file systems. This Linux Data Recovery tools is compatible with almost all Linux distributions like Gentoo, Turbo Linux, SlackWare, SUSE etc.

Root device refers to the device from which a Linux system boots from. While booting if you are getting errors that system cannot access or open the root device, you might need to install a fresh copy of operating system. Thus, you are always suggested to maintain a good data backup of all valuable information you have stored. In such situations, you probably loose data and if backup fails to restore, you will need to use Linux Data Recovery software to scan and restore the data.You might receive the similar error message while attempting to boot your system: "Cannot open root device "nnn" or unknown-block(maj,min) Please append a correct "root=" boot option"Where, 'nnn' represents the name of device and 'maj,min' is the address value of block. You cannot boot your system after you receive this error message.CauseSome of the possible reasons for this error message to occur are:* Incorrect entry in grub.conf file* Incorrectl configured kernel* SCSI controller or IDE chipset support is either not compiled or is compiled as a module instead of initrd* File system support is either not compiled or is compiled as a module instead of initrd* If you have recently installed the system, then the odds are that you haven't edited /etc/fstab file while installing. fstab is the file referenced by Linux to determine available disks and disk partitions and is most commonly used by mount command.SolutionTo solve such issues, you need to boot your affected system using Linux Live CD and check and reset the faulty parameters that are preventing your Linux system from booting. If this doesn't help, you should reformat and reinstall the system as the last resort. You can then restore your lost data from the most recent data backup you have. But backup availability is not must in each case. In such situations, you are recommended to use Linux Recovery software. Linux Data Recovery applications are advanced applications that are specifically designed to scan a lo gically crashed drive. After a thorough scan, they restore lost data at a safe location, without harming actual data.Stellar Phoenix Linux Data Recovery is a powerful Data Recovery Linux software that supports Ext2, Ext3 and ReiserFS file systems. It is a non-destructive tool with rich user interface and advanced recovery abilities. It natively supports all Linux distributions like Red Hat, Turbo Linux, SlackWare, Caldera, Sorcerer, SUSE etc.

Partitioning a Linux based hard drive means dividing it into many logical drives, each of which is considered as an independent disk. Linux supports different disk partitioning software such as cfdisk (curses based version of fdisk), parted (GNU partition editor), sfdisk (command line version of fdisk) and of course the basic one, fdisk. At times you encounter errors that force you to remove all the existing partitions. In such situations, it becomes essential that you use your recent data backup and restore the lost information. But sometimes, you find that your backup is not as productive that could offer complete data restoration results. Thus, to overcome such situations, you need to use Linux Recovery tools. While trying to execute cfdisk as root to perform tasks like formatting the partition, you get the similar error message on screen:"FATAL ERROR: Bad primary partition : Partition ends in the final partial cylinder"* cfdisk is an improved curses based version o fdi sk. This Linux partition editor is a part of util-linux package included in Linux utility programs. CauseThe above error message occurs if the existing partitions are not in correct layout. cfdisk gives this error message when it detects hard drive partitions in bad order or overlapped. Solution To fix the above issue, you should correct the present disk layout. You can perform this by removing all the existing partitions and creating new ones. To do so, use any of these methods:* Try using cfdisk -z /dev/device command* Make use of disk partitioning utilities like fdisk, gparted etc. You may fail to repartition the hard drive using cfdisk as it prompts errors until it finds issues with disk layout. Using any of the methods, described above, all the data that exists on disk gets deleted. Therefore, to restore the lost information, you should check your data backup status and restore from it. If backup cannot give the required results, scan your disk using Linux Data Recovery applications. Linux Recovery software are specifically designed tools to locate the missing information and restore it safely. In addition, you find these products with interactive interface equipped with rich graphic tools. Stellar Phoenix Linux Data Recovery is the finest Linux Recovery utility. It incorporates powerful scanning algorithms, read-only design, intuitive interface and advanced features. It supports data recovery for Ext2, Ext3 and ReiserFS file systems. It is compatible with most of the Linux distributions- Red Hat, SUSE, Caldera, Mandrake, TurboLinux, Slackware, Gentoo etc.

LILO (LInux LOader) is the standard boot loader used for Linux systems. When you start a LILO installed system, it undergoes two major stages to boot successfully: first stage (in boot sector) and second stage (in /boot/boot.b file). LILO finds all the required sector addresses in a map file called /boot/map, which is created when you install LILO. With the success of each stage while booting a LILO installed system, it displays a letter. It implies if it is displaying complete word-LILO, the boot process is successful. If the process encounters any discrepancies, it will halt displaying an error on screen. In critical situations, you might need to reformat the drive and use your recent data backup or Linux Recovery tools to restore lost data. As an instance, when you start a Linux-based system, it might the letter 'L", followed by a 2-digit error code. The error code could be 01, 07, 0C etc. CauseA Linux system displays the letter 'L' when the first-stage boot loader load s successully but it cannot continue to load second stage boot loader. The general causes for such errors to occur are bad parameters in BIOS, geometry mismatch, LILO corruption and media failure issues. However, to determine the exact cause, you should refer to the 2-digit error code following the letter 'L'. SolutionTo troubleshoot such problems, you can try performing steps like:* If LILO is corrupted, remove and reinstall it. To remove LILO, use this command:lilo -u /dev/hdaFor reinstalling LILO, run LILO command as root. * You can try specifying linear option at the top of /etc/lilo.conf file.* You should check your BIOS setting to make sure that the specified hard disk geometry matches with that of your hard drive. You can use the following command to get the hard drive geometry details:hdparm -g /dev/hda* Try putting LILO on a different partition and making it bootable by using fdsik. * Run fsck, hard drive might be corrupted. Reforat the hard drive if fsck doesn't re solve the issue. You will need to use your backup to restore lost information the hard drive or use Data Recovery Linux tools after reformatting. Designed with powerful Linux Recovery algorithms, these utilities serve as safe products to recover lost data. Stellar Phoenix Linux Data Recovery is a comprehensive tool to recover lost data. It supports Ext2, Ext3 and Reiser FS file systems. With advanced options like RAW File Recovery, Disk Imaging, File Filter etc., it is a user-friendly application. This Data Recovery Linux tool is compatible with almost all Linux distributions like SUSE, Red Hat, SlackWare, Turbo Linux, Gentoo etc.

Will Windows 8 block users from dual-booting Linux? Microsoft won't say

Some are concerned that Microsoft's coming Windows 8 secure-boot technologies and policies could result in users being unable to dual-boot Linux alongside Windows 8. Microsoft officials aren't commenting on whether the worries are unfounded or grounded.

There's a report circulating -- originating with a Red Hat employee -- that says Microsoft's new secure-boot functionality in Windows 8 could preclude users from running both Windows and Linux on their PCs.

True or false? Well-grounded or unfounded? Microsoft execs will not comment -- which is leading many to assume it's true.

Matthew Garrett, a power management and mobile Linux developer at Red Hat, blogged about the possible lock-out scenario on September 20. He explained how the Unified Extensible Firmware Interface (UEFI) technology and Microsoft's secure-boot plans -- outlined in a new blog post on the "Building Windows 8 blog this week -- potentially could thwart those who want to dual boot Linux and Windows 8 on their Windows 8 machines.

Garrett's conclusion: "It's probably not worth panicking yet. But it is worth being concerned."

Microsoft officials have said -- via a UEFI session at the company's recent Build conference, along with the aforementioned blog post -- all that they are going to say on the topic.

Here's what Microsoft has said, re: its secure boot plans for Windows 8. These tidbits are from the previously mentioned Build session on UEFI:

All firmware and software in the boot process must be signed by a trusted Certificate Authority (CA)Required for Windows 8 clientDoes not require a Trusted Platform Module (TPM)Reduces the likelihood of bootkits, rootkits and ransomwareAnother slide from the same talk:

Garrett's interpretation of Microsoft's shared information on the topic:

"Microsoft requires that machines conforming to the Windows 8 logo program and running a client version of Windows 8 ship with secure boot enabled. The two alternatives here are for Windows to be signed with a Microsoft key and for the public part of that key to be included with all systems, or alternatively for each OEM to include their own key and sign the pre-installed versions of Windows. The second approach would make it impossible to run boxed copies of Windows on Windows logo hardware, and also impossible to install new versions of Windows unless your OEM provided a new signed copy. The former seems more likely.

"A system that ships with only OEM and Microsoft keys will not boot a generic copy of Linux."

I can't resist a rant here: The Windows team's decision not to comment on this report is an example of the new communication strategy that Microsoft seems to be instituting with Windows 8: Clarification on any Windows 8 topic -- not only features and policies that are still unannounced, but also those that already have been disclosed publicly -- apparently will not be provided by anyone from Microsoft in an official capacity. The result: An increasing amount of misinformation about Windows 8 is circulating, and Microsoft is doing little or nothing to correct it.

I understand Microsoft's increased desire for secrecy around its Windows plans, somethingcompany officials began pushing post-Vista. (I haven't always agreed with the goal, especially when it results in FUD for customers attempting to make rational buying decisions or OEM/ISV partners attempting to build products that work with Windows.) But allowing wrong information to go unchecked in the name of wanting to control the message and the way it is delivered seems like bad business to me.

Back on topic: Does anyone out there have any more to share (in an official capacity or not) about whether you think the new Windows 8 secure boot technologies and policies will block users from dual-booting Linux? Ars Technica's take: "Ultimately, the Windows 8 changes aren't likely to wipe out Linux dual-boot scenarios, but they could restrict the types of hardware that will allow them." Other opinions?

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