Creating iSCSI initrd

[Kedarka]

mkinitrd script in FC6 is able to create initrd with iSCSI support. Does anyone know whether there is any reasonable way to force it to create initrd with iISCSI support without actually having root on iSCSI?

[brunson]

Try reading the first two paragraphs under "Description" on the mkinitrd man page and post back if you need more help.

[Kedarka]

You mean these two paragraphs

DESCRIPTION
mkinitrd creates an initial image used by the kernel for preloading the
block device modules (such as IDE, SCSI or RAID) which are needed to
access the root filesystem. mkinitrd automatically loads filesystem
modules (such as ext3 and jbd), IDE modules, all scsi_hostadapter
entries in /etc/modprobe.conf, and raid modules if the system’s root
partition is on raid, which makes it simple to build and use kernels
using modular device drivers.

Any module options specified in /etc/modprobe.conf are passed to the
modules as they are loaded by the initial ramdisk.


?

I do not see any point how this relates to my question. I know what mkinitrd is but I am asking whether there is a way how to force mkinitrd to create ramdisk as if root were located on iSCSI device. I'm preparing initrd ramdisk for diskless boot and thought thath mkinitrd could be used as it has the ability to do it.

[brunson]

What would be different about a machine that has its root filesystem on an iSCSI disk than a machine that has its root on a local disk? Modules and mount point.

Modules are specified in /etc/modprobe.conf and mountpoints are specified in /etc/fstab. Mkinitrd reads /etc/modprobe.conf and accepts a command line switch for an alternate fstab.

[Kedarka]

The difference is, that it is not enough for iSCSI to have modules and mountpoint.
The initrd needs also driver for proper network card, needs to start the network card (i.e. it may need dhcp client), it needs at least iscsistart binary (static one) and needs to run it, then wait for successfull connection and then it can mount the mountpoint.
And the initrd ramdrive needs to contain the information about network configuration, iSCSI target and CHAP secrets.

[brunson]

You're right, I was oversimplifying the problem.