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Grub is grub, there will be no major differences in how this is done because it is a server, laptop, desktop, etc. Just be careful with mount points since they can be different based on the hardware you are using, and if the original setup was done using LVM (logical volumes in Red Hat) or physical paths (for an HP Smart Array it will likely be /dev/cciss/xxx).
Well this probably isn't what you want to hear, but both options could be right, or neither of them could be right. Think about what is happening when the server is booting for a minute to help understand. When you hit the power button the BIOS will do a POST, and after all subsystems BIOS will begin to pass control (in the specified order) to various devices until it finds one which has instructions on how to boot. In this case it is a drive with Grub on the MBR. Grub then knows where the OS is installed, and how to start booting the default (or selected) kernel.
The thing you will need to know is where was Grub originally installed, and where is your OS installed? The grub commands listed are just specifying to install the Grub bootloader on the first drive in the system. This will generally be the default, but there is no reason that things might be setup differently in your case. Have you been able to boot to a live CD and look at the drives and see how what partitions exist with data still in tact? That should help ensure we are now configuring Grub properly.
Erik, I plan on booting Ubuntu today. Not really sure what I should expect to see as far as data goes. By that I mean, I'm used to Windows environment where I can view individual drives, folders, files.
Are there commands I can use, or even in the GUI environment to be able to tell what version of Linux I have?
In the few times I've seen this machine booting up, I recall Redhat displayed, but can't recall the version/release, etc.
I tried typing sudo grub and command wasn't recognized. Then I typed just grub and it says grub isn't installed and gave me command to do so.
In GUI interface I opened folders and see GRUB listed....is this the same thing?
I don't have admin rights to look at some of the folders and they aren't named, so although I see GRUB listed, I don't know on which drive it resides.
More info......
Under Places>Computer> I attempt to open /home and /temp and get error message "Unable to mount location- No mount object for mounted volume"
Under /boot I can view files/folders.....GRUB is listed first.
Then under System>GParted??>.......wasn't really sure what I was looking at, but window shows following columns:
Partition
File System
Mount Point
Label
Size.....etc....
The path /dev/cciss/c0d0px are the physical devices, not the mount points. Each of those is a partition, and you will need to determine which one of them is mounted as what. The easy way would be to look for a file on the disk /etc/fstab which has all of these mappings. Also this isn't making complete sense when matched with the output of the controller having three arrays, the Gparted is showing as having multiple partitions but on a single logical drive. Now this either means you possible missed the other arrays when you first looked, some data has been lost, or those drives were never in use.
Some of the problems you are having are likely due to permissions, so it might be easiest to mount the drives using the live CD again, but this time use a terminal to run some tests. First I would say do a sudo fdisk -l, which should list all devices and partitions on those devices. Obviously for this exercise we are only interested in the drives in those which are on the array which was in use prior. Then you can do a sudo df which will show how the live CD mounted the partitions so they can be accessed. Then you can use commands such as sudo ls to check the integrity of data on the partitions.
Also using an Ubuntu live CD to fix grub of a Red Hat server might not be the best idea as Ubuntu is more latest packages where as Red Hat is all about stability and generally uses older versions. Is this server still under contract with Red Hat? Do you have access to the original install CD/DVD, using that to repair grub will probably give you the best compatibility and reduce potential from problems when doing future Red Hat updates.
I have not used an Ubuntu live CD recently. Yes the files and directories for grub in /boot are what is relevant to booting the system. However what we need to verify is if the /boot you are seeing is the version from the CD or one of the actual drives. You also then need to go further and make sure that one of the three logical drives has a MBR with grub installed.
df will just list the mounted partitions/drives:
/dev/sdb2 8649576 4575408 3634792 56% /
You should see multiple lines like the above, this is just showing that /dev/sdb2 is used with a mount point of / (the root partition). What you want to see is which physical devices are mapped to which mount points, and then inspect the original /boot and make sure everything there is readable and in tact. You can also verify that the logical volume which has /boot has a MBR and is marked as bootable.
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