- Boot your server as usual, but you need to get to the SYSLINUX prompt by pressing the <shift> key after BIOS POST.
- You will then see the Syslinux boot: prompt which is asking you for which kernel it should boot. You need to then type menu.c32 <enter>. Be warned that a hidden boot timer is ticking at this prompt, but it's reset every time you type a key.
- You will be presented with a menu for booting into e.g., regular XCP, safe mode, etc. Select the first entry (xe) with the cursor keys (it should start on that entry anyway), then press <Tab> to edit the boot parameters.
- You should see something like the following:
append /boot/xen.gz dom0_mem=752M lowmem_emergency_pool=1M crashkernel=64M@32M console= vga=mode-0x0311 --- /boot/vmlinuz-2.6-xen root=LABEL=root-mlbdhhzz ro xencons=hvc console=hvc0 console=tty0 quiet vga=785 splash --- /boot/initrd-2.6-xen.img
- You want to insert the single keyword for the dom0 kernel like so:
append /boot/xen.gz dom0_mem=752M lowmem_emergency_pool=1M crashkernel=64M@32M console= vga=mode-0x0311 --- /boot/vmlinuz-2.6-xen single root=LABEL=root-mlbdhhzz ro xencons=hvc console=hvc0 console=tty0
quietvga=785 splash--- /boot/initrd-2.6-xen.img
I also removed the quiet and splash options so that I can see if anything strange is happening during the boot process.
This should drop you at a single-user root prompt from which to do your analysis and repair.