Missing operating system, missingoperating

Missing operating system, missingoperating

Use UltraISO to create a Red Hat Enterprise Linux Server release 5.7 USB flash drive, and then install it on a PC. Some options are not detailed during installation. After the installation is complete, an error is reported when you start the system:Missing operating system.

Plug in the USB flash disk and choose to start the system from the USB flash disk in the BIOS. After searching for some information, it is found that during the installation of the LINUX operating system, the USB flash disk is used for installation, the guided grub information is installed in the USB flash drive by default (this is often not noticed). After the USB flash drive is removed, the startup process cannot read the code of the corresponding startup manager, causing the system to fail to start. GRUB is described as follows:

GRUB is called Grand uniied Boot Loader and is the mainstream Boot guide manager in Linux. The main function is to start and load the Linux operating system. After BIOS self-check is completed during system startup, GRUB will be loaded immediately. The GRUB contains the code that can be loaded into the operating system and the code that passes the operating system boot permission to other boot guide managers. GRUB allows users to select different kernel to start the system, or set different startup parameters during system startup.

As shown in, The grub Installation option of Linux is "The GRUB boot loader will be installed on/dev/sdb" by default ". This/dev/sdb device is exactly my USB flash drive.

Some information on the internet describes how to solve this problem, that is, insert a USB flash disk. After the operating system is started successfully, perform the following operations on the terminal:

[root@localhost ~]# grub

Probing devices to guess BIOS drives. This may take a long time.

    GNU GRUB  version 0.97  (640K lower / 3072K upper memory)

 [ Minimal BASH-like line editing is supported.  For the first word, TAB

   lists possible command completions.  Anywhere else TAB lists the possible

   completions of a device/filename.]

grub> root(hd0,0);

root(hd0,0);

Error 27: Unrecognized command

grub> root (hd0,0);

root (hd0,0);

 Filesystem type is ext2fs, partition type 0x83

grub> setup (hd0)

setup (hd0)

 Checking if "/boot/grub/stage1" exists... no

 Checking if "/grub/stage1" exists... yes

 Checking if "/grub/stage2" exists... yes

 Checking if "/grub/e2fs_stage1_5" exists... yes

 Running "embed /grub/e2fs_stage1_5 (hd0)"...  15 sectors are embedded.

succeeded

 Running "install /grub/stage1 (hd0) (hd0)1+15 p (hd0,0)/grub/stage2 /grub/grub.conf"... succeeded

Done.

grub> quit

quit

[root@localhost ~]# 

Then modify vi/etc/grub. in the conf file, change hd1 to hd0. In my test, there is no/boot/gurb/grub at all. the configuration file conf is related to the operating system version.

 

[root@localhost ~]# vi /etc/grub.conf 

# grub.conf generated by anaconda

#

# Note that you do not have to rerun grub after making changes to this file

# NOTICE:  You have a /boot partition.  This means that

#          all kernel and initrd paths are relative to /boot/, eg.

#          root (hd1,0)

#          kernel /vmlinuz-version ro root=/dev/VolGroup00/LogVol00

#          initrd /initrd-version.img

#boot=/dev/sdb

default=0

timeout=5

splashimage=(hd1,0)/grub/splash.xpm.gz

hiddenmenu

title Red Hat Enterprise Linux Server (2.6.18-274.el5)

        root (hd1,0)

        kernel /vmlinuz-2.6.18-274.el5 ro root=/dev/VolGroup00/LogVol00 rhgb quiet

        initrd /initrd-2.6.18-274.el5.img

title Other

        rootnoverify (hd1,3)

        chainloader +1

[root@localhost ~]# more /etc/grub.conf 

# grub.conf generated by anaconda

#

# Note that you do not have to rerun grub after making changes to this file

# NOTICE:  You have a /boot partition.  This means that

#          all kernel and initrd paths are relative to /boot/, eg.

#          root (hd1,0)

#          kernel /vmlinuz-version ro root=/dev/VolGroup00/LogVol00

#          initrd /initrd-version.img

#boot=/dev/sdb

default=0

timeout=5

splashimage=(hd0,0)/grub/splash.xpm.gz

hiddenmenu

title Red Hat Enterprise Linux Server (2.6.18-274.el5)

        root (hd0,0)

        kernel /vmlinuz-2.6.18-274.el5 ro root=/dev/VolGroup00/LogVol00 rhgb quiet

        initrd /initrd-2.6.18-274.el5.img

title Other

        rootnoverify (hd0,3)

        chainloader +1

After modification, restart the operating system to solve the problem. In addition, no grub operation is required during the test. You only need to modify/etc/grub. conf to solve the problem. In addition, I specifically tested "No boot loader will be installed" during the test. After reboot is installed, the following interface will appear. You can go to grub and follow the steps above to solve the problem.

References:

Http://blog.sina.com.cn/s/blog_5e48f39c0100jmwp.html

Http://www.cnblogs.com/darktime/p/3404584.html