Creating an EFI partition on a device, from EFI.

[The Brit]

Can anyone give me a link to the EFI User Guide/Manual?

I want to know if it is possible to create an EFI partition on a disk device, from the EFI level.

I am using OpenVMS. I am examining the )(hypothetical) situation where I have a disk which I know contains the OS, but for some reason, it has no EFI partition and so it appears as a "blk" device and not an "fs" device.

If I can identify the device (by controller and lun), is there anyway I can write an EFI partition on the disk from the EFI level, and then boot from it??

I guess I am looking for the EFI equivalent of WRITEBOOT, if it exists.

Any ideas? (and/or the EFI manual link)

thanks.

Dave.

[Hoff · Accepted solution]

The equivalent command to writeboot is setboot.

You're presuming OpenVMS knows about partitioning, and it (mostly) doesn't.

This isn't feasible without a whole lot of work.

Yes, you can create partitions at the Shell. The EFI manual for the 1.10 environment and such was available over at Intel.

Now for the problem. The EFI GPT pieces and EFI itself don't know about ODS-2/ODS-5, and ODS-2/ODS-5 don't really know about GPT. And OpenVMS doesn't "do" disk partitioning. And EFI expects disk partitioning.

ODS-2 and ODS-5 and EFI and GPT have a truce.

Not an understanding.

If you don't understand this stuff after reading the following articles, let me know:

http://64.223.189.234/node/192
http://64.223.189.234/node/343
http://64.223.189.234/node/209
http://64.223.189.234/node/112
http://64.223.189.234/node/28

That last one has a whole write up on low-level disk structures and disk processing as related to creating CD and DVD and bootable media.

The real world fix for your hypothetical sequence is to boot InfoServer or vKVM/vDVD/vWhatsit or otherwise boot up an OpenVMS disk or distro and access its tools. You can't jam an EFI partition underneath OpenVMS from the level of EFI; I went out of my way to try to keep EFI users from doing that by the way the MBR and MBR/GPT partition records are created by setboot.

[The Brit]

Thanks Hoff,
Your answer is just about what I expected. I am comfortable with the other options, vis. vMedia, Enclosure DVD, Internal Disk, etc. so I'm not too upset. I was really just trying to confirm that this was not an option.

(I am putting together some local documentation)

I would still appreciate a link to the EFI manual (if such a thing exists)

Thanks again.

Dave.

[Hoff]

There are several different things that could be considered an EFI manual.

There is the low-level EFI specifications that are available over at the Intel web site. Those are located starting here:

http://www.intel.com/technology/efi/

There's also a FAT specification over there.

There are also EFI operational- and user-level documents for (some of) the EFI commands at the Shell, and at the BMC and iLO/iLO2 layers. Those documents are generally part of the HP platform documentation for whichever box is specifically involved. HP layered in its own POSSE stuff that seems intended to make EFI seem more like PA-RISC, and you'll only find that stuff documented via HP. Those documents can be located via the HP product support web site for the particular widget involved.

Here's the BL870c:

http://docs.hp.com/en/AH232-9008A-ed3/index.html

[GuentherF]

Dave, how did you end up with an Itanium system disk and no EFI partition?

The EFI partition on an OpenVMS/Itanium system disk needs two things:

- The container file of the EFI partition SYS$LOADABLE_IMAGES:SYS$EFI.SYS.

- A Global Partition Table [000000]GPT.SYS.

Do you find both on this disk?

/Guenther

[Hoff]

Guenther's comments to the contrary, it's quite possible to have a fully functional and bootable OpenVMS I64 system disk without having a GPT around. (Or it was.)

It's also possible to end up with a disk on an Integrity box that thinks it has a valid GPT, and really doesn't; that has a rogue GPT, at least as far as the rest of the software stack.

Depending on the OpenVMS release, there are a couple of paths where you can end up with a GPT that OpenVMS knows about, and a GPT that EFI knows about, and they don't match. That then led to various diagnostics being inserted into various code-paths. (Yeah, I missed a case.)

EFI has one view of the universe. OpenVMS has a different view. When correctly configured, these two views can and should align. But the real limit here is that the OpenVMS device drivers and the Primitive File System don't have support for partitioning.

[The Brit]

Although, as I pointed out early in the thread, I was discussing a hypothetical situation, it is perfectly reasonable to find your self in the position of having a bootable OS disk that has no partition on it.
Consider,

1. Image backup of system disk to internal drive.
2. Fail to run "boot_options" and add partition to copy.
3. Remove internal drive and install in different server.

the fact is that the copy is perfectly usable as a system disk, if only you could see it at the EFI level. Unfortunately, it is not visible because there is no partition on it.

the only way to use this disk is to first boot via some other means (CD or VMedia) and then use Boot_Options at the OS level to create a boot option/partition.

I think that Hoff answered my question, and the answer is (currently) NO.

Dave.