How To's and Gotchas in grub2 menus

These are my notes below, which may be of interest to those of you writing grub2 (or even grub4dos) menus.

Most of these are concerned with directly booting from a linux ISO file using 'cheat codes'.

If that does not interest you, then don't read any more.

Note: I have been learning and experimenting with grub2 for a week now, so I am by no means an expert!

Easy2Boot website now routed via ezoic

I have now signed up with ezoic.com who will re-format the easy2boot.com pages and place ads on the pages for me automatically.

You may experience some very weird page layouts on the E2B site in the next few weeks! Ezoic will trial lots of different formats until it finds the 'best' ones - this may take several months!

Note that a cookie is saved on your first visit which determines what layout you see after that. If you delete the site cookie, you may (randomly) get a different layout on refresh (Ctrl+F5).

Ezoic is also used on the www.rmprepusb.com website. I am hoping it doesn't screw-up the easy2boot site as much as it does the rmprepusb site!

E2B v1.80 available

I have released E2B v1.80j as the release version 1.80 today.

Links on the website will still point to 1.79 for  a few days, but 1.80 is available on the Alternate Download sites (Google Drive and OneDrive).

grub2 menu system testing continues (pre-Beta2)!

I have been testing, reviewing and fixing a lot of menus in the grub2 menu system.

Here is a spreadsheet of the testing so far.

x = does not work
(blank) = not yet tested

click to enlarge

Beta2 should be coming in a day or so...

As you can see, every payload needs to be tested on 4 different VMs and on two types of partitions (NTFS and FAT32)!

Booting Dr.Web LiveDisk ISO with persistence from grub2

A DrWeb_Persistent.imgPTN23 file can be found here. It was made as follows:
1. Make a 800MB FAT32 partition on a USB drive
2. Download and run the DrWeb USB creator utility drweb-livedisk-900-usb.exe
3. Run it to extract the files to the USB drive
4. Boot the USB drive on a real system - this prepares it
5. Refresh the updates - reboot and check updates are persistent
6. Drag-and-drop the USB drive letter onto the MPI_FAT32 Desktop icon to make a .imgPTN23 file (syslinux 603, auto-convert). I modified the \syslinux\txt.cfg and the \boot\grub\grub.cfg files to add nomodeset vga=ask ignore_uuid. 

Note: Updates are not persistent even on their own flash drive!  So it obviously has a bug!

Booting from ISO

The Dr.Web ISO boots fine in MBR mode from E2B and can be booted from the ISO with persistence by adding a .mnu file.

However, during testing of the new GRUB2 menu system for E2B, I tried the Dr.Web LiveDisk ISO (drweb-livedisk-900-cd.iso - free), but it did not boot using the grub2 menu that I 'borrowed' from the 'Multiboot USB Flash drive' project here (I got a 'squashfs not found' type error).

After many attempts to get it booting from an ISO using the cheat code 'iso-scan/filename=', I finally looked at the 'casper' linux shell script file located inside the initrd file in the scripts folder (using 7Zip), and found this code...

Grub2 menu system for E2B - early Beta available

The first Beta (Beta1  v0.01) is available for testing!

Please contact me if you want a copy to test. You will need a E2B USB HDD with a second partition.

It is possible to use this system on a Removable flash drive (but it is complicated because Windows cannot access the 2nd partition!).

Details are now published (in an early form) on the easy2boot website at http://www.easy2boot.com/uefi-grub2-ptn2/

Note that most of the linux menu items have been tested, but many of the other menus have not been tested with any payload at all yet.

MBR Main Menu

Grub2 support in E2B - progress report...

I have been spending quite a while thinking about the grub2 menu structure and it seems some people put E2B on the 2nd partition of their USB drive instead of the first partition. I don't advise this because of the 137GB BIOS bug, but as long as the 2nd partition ends before 137GB, it should work OK.

For payload files to be detected by the grub2 menu system, they must have specific lower-case names (e.g. avg.iso, konbootx64.efi). Files with names such as avg_arl_cdi_all_120_150814a10442.iso or "AVG AntiVirus.iso" will NOT be detected by the default grub2 menu system.

So there will be a large list of specific payload file names which I will document at a later date. As a consequence, you can only have one version of any ISO (though you can add your own uniquely-named payloadfiles and add your own grub2 menu for it).

Coming soon! grub2 UEFI-booting from linux ISO files using E2B

Currently you cannot directly boot from an ISO file via UEFI using Easy2Boot - you have to convert the ISO to a .imgPTN file first.

However, grub2 can UEFI-boot and can run linux ISOs (some of which will run even if the ISOs do not support UEFI-booting and do not contain an \EFI folder!).

The reason E2B does not use this mechanism is that some UEFI systems will only UEFI-boot from a USB disk containing both MBR and UEFI boot files - even if the system is set to boot from Legacy/BIOS devices.

This means that if you had grub2 UEFI boot files on your FAT32 E2B drive, then you can never boot to the E2B menu on these systems!

E2B not booting on GA-73PVM-S2H PC

Samir contacted me about a problem he had with his GA-73PVM-S2H PC.

He could boot from this PC to a USB drive prepared using Rufus (to Elemetary OS, for example), but not if it contained E2B.

The symptom was that the PC would just hang with no keyboard response or boot messages of any kind, as soon as he tried to boot from the E2B USB drive...

ESET + persistence from ISO

I finally figured out what the problem was with the ESET SysRescue ISO+Persistence menu that I did have working but then didn't work when I retested it. I had missed out the lines in the .mnu file which set the UUID of the 'live-media' - this meant that the live-media value was invalid and so it resorted to the CD updates. Also, you need to copy the ext3 partition from a working Eset flash disk (I cannot figure out what it is in a working ext3 image that is different from a non-working image made using RMPrepUSB 'Make ext2 FS' and copying over contents)!

I have also edited the menu now in the previous post (see lines in red).

So you can now boot from ISO with persistence if you wish, instead of using a .imgPTN file.