How can I clone a single HDD bootable disk from a Software RAID1 Array in Linux server? It is currently a two-disk HDD mirror array. I have physical access to the server, and it has empty bays for disks. I'd like to leave the RAID1 array the way it is, and just make a single cloned disk of the Linux OS (CentOS 7) and all the data.
I plan on migrating from CentOS 7, which is EOL, and want to use a cloned disk to do so. Then I'd like to create a RAID1 array starting with the new disk to replace the current one.
I've found instructions for removing a disk from an array safely, which I suppose I could do and then clone it (using Clonezilla). However, it would be simpler, I think, to leave the array operational and just clone from it, if possible.
And if I do need to remove the disk from the array, marking it as 'failed' ala instructions such as these, will the disk be bootable when I remove it, so I can create a bootable clone?
Thanks for any help.
You can use Clonezilla to create an image using Linux mdraid as a source without removing anything from the raid. Just boot your system from Clonezilla boot media and select mdXXX as a source. You can then restore the image onto something else and Clonezilla is smart enough to regenerate GRUB entries for you using appropriate UUIDs.