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45

One rare possibility could be you triggered some of the infamous UEFI bugs, that already killed some series of Samsung and Lenovo notebooks. It works like this: UEFI specs propose a non volatile memory (nvram or eeprom) that can be accessed by the OS to store settings or debugging information. Linux actually uses this feature in case of a kernel panic: If ...


27

No, it is not possible to destroy the BIOS (legacy or UEFI) in this manner with that command. Even if you somewhat managed to destroy the UEFI partition, core BIOS files will not be affected, as they reside in non-volatile memory (flash-based, mostly) socketed on your motherboard. UEFI partition hosts additional software components (eg: debugger, driver, ...


13

All IBM uEFI Machines take ages to boot, as after the eon-taking uEFI initialization and module startup the legacy BIOS emulation kicks in and the PCI-E option ROMs get executed etc. etc. This is "normal" on all IBM uEFI machines - no matter if blade or standard rack server. You could disable legacy BIOS boot, the option ROMs, optimize the boot order and ...


10

While fun, rm -rf / can only break a havoc inside its own little jail -- and that is the partition(s) it is given. It cannot mess up disk MBR, nor it cannot magically destroy your computer. Something else is wrong in your case.


10

When you say "EFI-only partition table" I suspect you're talking about a GUID Partition Table (GPT). Per Microsoft, Windows 7 and Windows Server 2008 can boot from a GPT, provided you're running an x64 build in a system with UEFI firmware.


8

The other answers seem to agree that wiping the BIOS is probably not your problem, so here's another thought: My computer, when switched into UEFI mode, skips the BIOS screen completely. No manufacturer's logo, no nothing. It just tries to boot and tells me there's no bootable media (or boots). If I remember the key to enter setup, I can whack it as the ...


7

This is probably too late to be of any use to Massimo, but i thought i would mention that i managed to get this to work, admittedly through a somewhat forced procedure: Enable the LSI Logic SAS driver on the original server Copy the raw drive via dd from a Linux live CD Convert the GPT to a hybrid MBR/GPT using GPT fdisk Boot the VM from the Windows DVD ...


6

Firstly you mean GPT vs. MBR, not EFI vs. MBR - one's a firmware, the other a partition type. The only part it plays in your question is that, in general, you need an EFI/UEFI firmware based system (rather than a BIOS based one) to boot from a GPT partition, although that can be worked around sometimes. Anyway a few things, DON'T EVER USE RAID 0, seriously ...


6

In short, yes and no for a few different reasons. If Windows is booting from a GPT disk, it must be from UEFI. Windows boot manager and loader cannot boot to MBR disk from native UEFI. However, if the UEFI is configured for legacy BIOS boot mode then an MBR disk can be used for booting. This stems from the Windows boot mode (BIOS with MBR or UEFI with ...


6

From my understanding an EFI partition on a Linux server ensures a standard for the disk layout Ah, yeah. So you think laptops are super special? The EFI partition is part of the UEFI standard. Either you have an UEFI bios and use UEFI to boot, or you do not - and Laptop or Server is irrelevant. Let me quote from Wikipedia: It contains the boot ...


5

If you are getting to the EFI shell you likely already installed Ubuntu in EFI mode. The caveat I have found it that thought the OS installs fine using the grub-efi bootloader, an EFI boot entry for that boot loader is not written into the EFI variables correctly. This means the EFI firmware does not know how to load the boot loader and thus the OS and drops ...


5

Microsoft won't let you achieve your step; so address your goal instead. Microsoft erroneously conflates has an EFI partitioned hard disc with has EFI firmware. This is, of course, clearly wrong. It's quite possible — and indeed is becoming ever more desirable these days — to have an EFI partitioned disc on a machine that has old non-EFI ...


5

UEFI shouldn't add any efficiencies all by itself, since BIOS and UEFI are there to bootstrap a system from bare CPU to an OS, and provide a translation layer between the OS and the hardware once things are booted. UEFI has a lot more capabilities in this regard. It is entirely possible that VMWare (and the other VM vendors) will develop a hypervisor that ...


4

Well, after much searching, experimentation, and general frustration, I have basically come to the conclusion that Hyper-V does not currently support UEFI guests, even if the Hyper-V server is running in UEFI configuration. This seems to be supported by the fact that that recent builds of Windows Blue have what they call "Generation 2" VM's that include ...


4

EFI BC = EFI Byte Code. EFI Byte Code is a processor agnostic language for device drivers, PXE, and other EFI extensions so that the code can be written once and run on any supporting platform.


4

"Fixed" by commenting out the parts that use BIOS e801 and e820 maps. Not sure why the no-real-mode won't work. diff -ur orig/xen-4.0.1//xen/arch/x86/setup.c mod/xen-4.0.1//xen/arch/x86/setup.c --- orig/xen-4.0.1//xen/arch/x86/setup.c 2010-08-29 15:13:22.000000000 +0000 +++ mod/xen-4.0.1//xen/arch/x86/setup.c 2012-01-28 01:33:22.000000000 +0000 @@ ...


3

One simple method would be to simply perform a base install of Windows on a machine that doesn't support EFI, capture it with your image software and restore it to the real hardware. A good choice might be to build your base install in a VM. In earlier versions (ver < 6) of Windows didn't adapt well to be moved from one type of hardware to another. ...


3

dmidecode in linux is capable of pulling this information via EFI, there is a port available here http://gnuwin32.sourceforge.net/packages/dmidecode.htm which appears to be compiled after EFI support. The command would dmidecode -s system-serial-number as tested on my BIOS based system, however I'm unable to test fully as I havn't got an EFI system to hand.


3

CentOS 7 currently does not support running on Hyper-V Generation 2 virtual machines, as can be seen here. You have to recreate the VM and specify Generation 1 as the VM type. Linux Virtual Machines on Hyper-V provides a comprehensive list of which distributions are supported and any limitations associated with them. For a list of the differences between ...


2

Just adding more on EFI.. Like TomTom mentioned you either have BIOS or EFI (Extensible Firmware Interface) also called UEFI. When you use EFI based systems you use GPT partitions. GPT partitions can address a disk more than 2TB which MBR can not at the moment. This is one of the major reasons of using GPT partitions in EFI based systems. So when you ...


2

The first problem that you write in UNIX style. But the UEFI uses DOS style. So your sequence of commands: map mount blk0 aaa aaa: // !!! change disk in dos stile cd EFI\debian // use backslashes grubx64.efi // run bootloader without "./" The second problem - you have nothing written about the disk partitioning system. You can`t use ...


2

Hyper-V 2012 R2 generation 2 VM environments have UEFI firmware. See: http://technet.microsoft.com/en-us/library/dn282285.aspx http://blogs.technet.com/b/jhoward/archive/2013/10/24/hyper-v-generation-2-virtual-machines-part-1.aspx


2

So it looks like, for some reason or another, having the PXE firmware be first in the boot order (which is how it was when I first got the server) breaks UEFI booting. When I set UEFI:debian as the first entry in the boot order, it boots all by itself, no intervention needed. The downside, of course, is that if I need a rescue OS over PXE, I need to first ...


2

I agree the System X uEFI legacy implementation is so painfully slow, that I might even avoid selling them as a platform to my clients. Measuring the IBM form the time it starts a legacy USB key boot until I get an OS prompt is ridiculously long. I am using SmartOS (an illumos/opensolaris derivative for all intents an purposes once booted it runs and acts ...


2

ELILO: EFI Linux Boot Loader is very easy to implement and meets some of the criteria: ☑ Menus ☐ Sub-menus ☑ Linux kernel/initrd TFTP load (naturally) ☐ Arbitrary EFI application load ☑ Fallthrough to next boot option (eventually I'll document what's required to get it working end-to-end…)


2

I had just a similar problem. You could try IBM Serverguide v8.43. It worked well with SBS 2011 x64.


2

Take a look at this thread, particular the last post by BizCon Alex - http://communities.vmware.com/message/1695451 P2V conversion with EFI/GPT will be a nightmare unless someone comes out with a clean solution. EDIT: the other option is to use a commercial product such as DoubleTake Move (http://www.visionsolutions.com/Products/DT-Move.aspx). Replicate ...


2

You are not alone. This seems to be a bug with uefi and xen. No resolution thus far. xen-devel mailing list redhat bug


1

I have exactly the same issue with an Asus P8P67 board and xen 4.1.2. The workaround posted above (slightly adjusted to match 4.1.2 source) also fixed it for now. But I am missing the background knowledge to understand if this will have any consequences/instabilities. So far no trouble observed.



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