Joseph Spenner
2011-Dec-12 15:51 UTC
[CentOS] dd disk will not boot - can't find /dev/root
OS= CentOS 5.4, 64bit. I've always had great luck using dd to copy entire disks, and booting on other systems.? However, I'm having difficulty with a couple systems.? I boot using an install DVD so the OS disk is quiet, and dd to my target disk: # dd if=/dev/sda of=/dev/sdb bs=1024k /dev/sdb is the blank disk.? The disks are 2T.? After a few hours the operation is complete.? But when I try to boot the new disk on my other system, I get the following errors after the CentOS boot menu (it counts down to boot the default disk fine, then this error): ? (screen shot at?? http://img214.imageshack.us/img214/645/centosbooterror.jpg?? ) I've read posts regarding the /dev/root error, and they talk about rebuilding initrd.? I've tried some of the fixes mentioned, but have had no success. All I can think of is slightly different hardware on the new system where I'm trying to boot, but I'm not sure what the difference could be. They're both 64bit SuperMicro systems. If anyone has any ideas, I'd love to hear. Thanks!
Joseph Spenner
2011-Dec-12 16:01 UTC
[CentOS] dd disk will not boot - can't find /dev/root
________________________________ From: Joseph Spenner <joseph85750 at yahoo.com> To: "centos at centos.org" <centos at centos.org> Sent: Monday, December 12, 2011 8:51 AM Subject: [CentOS] dd disk will not boot - can't find /dev/root OS= CentOS 5.4, 64bit. I've always had great luck using dd to copy entire disks, and booting on other systems.? However, I'm having difficulty with a couple systems.? I boot using an install DVD so the OS disk is quiet, and dd to my target disk: # dd if=/dev/sda of=/dev/sdb bs=1024k /dev/sdb is the blank disk.? The disks are 2T.? After a few hours the operation is complete.? But when I try to boot the new disk on my other system, I get the following errors after the CentOS boot menu (it counts down to boot the default disk fine, then this error): ? (screen shot at?? http://img214.imageshack.us/img214/645/centosbooterror.jpg?? ) I've read posts regarding the /dev/root error, and they talk about rebuilding initrd.? I've tried some of the fixes mentioned, but have had no success. All I can think of is slightly different hardware on the new system where I'm trying to boot, but I'm not sure what the difference could be. They're both 64bit SuperMicro systems. If anyone has any ideas, I'd love to hear. Thanks! _______________________________________________ I just noticed the link didn't like my ( ).? The clickable link is:?? http://img214.imageshack.us/img214/645/centosbooterror.jpg
On Mon, Dec 12, 2011 at 9:51 AM, Joseph Spenner <joseph85750 at yahoo.com> wrote:> OS= CentOS 5.4, 64bit. > > I've always had great luck using dd to copy entire disks, and booting on other systems.? However, I'm having difficulty with a couple systems.? I boot using an install DVD so the OS disk is quiet, and dd to my target disk: > > # dd if=/dev/sda of=/dev/sdb bs=1024k > > /dev/sdb is the blank disk.? The disks are 2T.? After a few hours the operation is complete.? But when I try to boot the new disk on my other system, I get the following errors after the CentOS boot menu (it counts down to boot the default disk fine, then this error):If you do much of this, I'd recommend using the clonezilla-live distro which will automate it and use partclone to avoid having to copy the unused parts of the disk.> ? (screen shot at?? http://img214.imageshack.us/img214/645/centosbooterror.jpg?? ) > > I've read posts regarding the /dev/root error, and they talk about rebuilding initrd.? I've tried some of the fixes mentioned, but have had no success. > All I can think of is slightly different hardware on the new system where I'm trying to boot, but I'm not sure what the difference could be. > They're both 64bit SuperMicro systems. > > If anyone has any ideas, I'd love to hear.I suspect the hardware isn't really identical. Can you boot the source machine from the copied disk? -- Les Mikesell lesmikesell at gmail.com