Install 14.04 Desktop with second EFI partition

[geohei]

Hi.


geohei@deimos:~$ sudo gdisk /dev/sdb
GPT fdisk (gdisk) version 0.8.8

Partition table scan:
MBR: protective
BSD: not present
APM: not present
GPT: present

Found valid GPT with protective MBR; using GPT.

Command (? for help): p
Disk /dev/sdb: 500118192 sectors, 238.5 GiB
Logical sector size: 512 bytes
Disk identifier (GUID): 7B2A6511-D248-41E6-BB41-8F15451740AA
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 500118158
Partitions will be aligned on 2048-sector boundaries
Total free space is 38072941 sectors (18.2 GiB)

Number Start (sector) End (sector) Size Code Name
1 2048 206847 100.0 MiB EF00 Windows 7 (ESP)
2 206848 468991 128.0 MiB 0C01 Microsoft reserved part
3 468992 210184191 100.0 GiB 0700 Basic data partition
4 210184192 315041791 50.0 GiB 0700 Basic data partition
5 315041792 315246591 100.0 MiB EF00 Ubuntu 14.04 (ESP)
6 315246592 420104191 50.0 GiB 8300 Ubuntu 14.04
7 420104192 462047231 20.0 GiB 8200 Linux swap
I have a dual boot system installed on my SSD (GPT).
1. Windows 7
2. Ubuntu 14.04

I'd like to use a separate EFI partition for Ubuntu (for separate backup/restore operations and potential mutual interfeneces duer Windows 7 / Ubuntu EFI updates).

How can I instruct Ubuntu 14.04 during installation procedure to use sdb5 as EFI instead of sdb1?

Thanks!

[oldfred]

You cannot currently.

I understand UEFI spec does technically allow multiple efi partitions, but currently no system works with more than one efi partition per device.

But each install has a separate folder in the efi partition, so they are separate.

Typical structure in efi partition:

/EFI/Boot
/EFI/Microsoft/Boot
/EFI/ubuntu

[ubfan1]

Since the Ubuntu bootloaders are kept in a separate directory (/EFI/ubuntu), there is little chance of interference with the Windows bootloaders in /EFI/Microsoft/Boot/. Only one efi partition is allowed per device, but I don't know if just removing the boot flag would be enough to make the second one "invisible". Anyway, having to change the partition table to change OSes is a very dangerous thing, if you mess up the partition table, you really will be in recovery pain. Just use the supplied EFI partition (100M is smaller than I prefer, but really, even with Ubuntu bootloaders added, and a vendor backup in place, only about 55M will be used.

[geohei]

What do you think of this here: Move Ubuntu 14.04 Desktop ESP partition (http://www.geohei.lu/geoheiWP/?p=85)

It took me a while ... but it works!

[oldfred]

Glad you found a solution.

That is the first time I have seen anyone try to make two efi partitions work.

But I am not sure it really is needed anyway. He has multiple drives and a better configuration would be Windows on one drive and Ubuntu on another drive. then each hard drive would have its own efi partition without issue.

And the issue of backup can be controlled just by separately backing up the efi partition and making sure that backup occurs any time any other operating system install is updated or backed up.

[geohei]

He = me (I wrote the article) :p

I'm also not sure it's really needed. Time will see ... and for the updates ... a simultaneous update would indeed be a possible solution (let me think about that).