For a netboot cluster, I'm creating a CentOS 6.5 root disk. The goal is to mount /
read-only over NFS, and various other folders, such as /var/log
, on the local disk.
Here's my first idea:
On boot, a script is executed as early as possible, which checks whether the local disk needs to be initialized or not;
If the disk needs initialization, the LVM volumes are created;
Normal boot continues, and the partitions are mounted whenever
/etc/fstab
is read.
However, other than modifying /etc/inittab
or /etc/rc.d/rc.sysinit
, which doesn't sound quite reasonable, I can't see how to execute a script before /etc/inittab
is read.
As using local disks with a netboot setup seems to be a fairly common need, I wonder whether there is other solutions to achieve this behavior?
You'll probably want to do what you're looking for in a custom initrd. The initrd is used getting drivers loaded, getting software RAID up and going, etc. If you look around for diskless / stateless boot tutorials I suspect you'll be able to cobble together the pieces.