RHEL6.4 iSCSI boot with iPXE

[jrgruher]

Hello-

I am trying to boot RHEL6.4 over iSCSI using iPXE to start the boot process. I’ve done this before on boards which had BIOS iSCSI boot support and it works fine so I know RHEL6.4 supports iSCSI boot. However, I can’t quite seem to get it to work with iPXE.

My process is:
1. Boot RHEL installer from ISO
2. Mount iSCSI target using iSCSI support in installer GUI
3. Install RHEL as usual, no special settings
4. Reboot and boot from iPXE on USB key
5. Use iPXE script to configure network interface and sanboot from iSCSI target

It almost works… iPXE is able to configure the network and connect the target and begin the boot process. I can actually see RHEL loading for a while so I know boot has begun. However, before boot completes, it crashes as shown in the attached screenshot. My theory is this is happening when the iSCSI connection is handed off from iPXE to the native iSCSI initiator in RHEL, but that is just a guess, I don’t really have any evidence for that being the case.

Is this a known problem? Any known tips or tricks or workarounds I might try?

Thanks!

-Joe

[mcb30]

(2013-05-10 02:16)jrgruher Wrote:  It almost works… iPXE is able to configure the network and connect the target and begin the boot process. I can actually see RHEL loading for a while so I know boot has begun. However, before boot completes, it crashes as shown in the attached screenshot. My theory is this is happening when the iSCSI connection is handed off from iPXE to the native iSCSI initiator in RHEL, but that is just a guess, I don’t really have any evidence for that being the case.

Can you try removing "quiet" from the kernel command line (probably in /boot/grub/menu.lst on the iSCSI target volume)? It looks as though the relevant information is missing from the screenshot you posted.

Michael

[robinsmidsrod]

I think the first thing you need to do is increase the logging/debugging in your grub/kernel, because the only thing I see there is a partial stack trace that has something to do with syncing, which probably means it is unable to access some form of disk device. Try that and report back.

I believe I also saw this problem mentioned on IRC or the mailing-list, and that you might be doing it backwards.

If you're interested, there is an example on http://ipxe.org/examples to my boot menu that shows how to iscsi boot an Ubuntu 12.04 install. I'm sure the RHEL method should be similar (but probably not exactly the same).

[Torgeir]

Hi!

I am doing this with rhel 5.4 -> rhel 6.4 (PXE boot, kickstart installation to iSCSI drive, if macaddress does not have an iSCSI disk we run SSH (phpseclib ssh-keys) against NetApp and generate one). Not a problem for me.

The only thing is some specific machines (we use HP), need kernel parameters to boot correctly "acpi=off"...

Torgeir