Hyper-V Question -- Boot from file (shim.efi)

Hi Hyper-V Gurus.

Creating a Linux Guest on Hyper-V -- no problems -runs perfectly but looking at the VM settings seems the "boot device" is a file with the name shim.efi. I'd have thought that the Guest would have booted from the appropriate boot file, grub2/systemd in Linux or the efi partition on Windows.

Any idea or is it just how Hyper-V names a "foreign" e.g non Windows boot manager file.



Cheers
jimbo

Never really explored it, but it's likely it may contain required content to boot a hyper-v VM. EFI's can be chained so it may ultimately load another EFI that is part of the VM

jimbo45 said:

Hi Hyper-V Gurus.

Creating a Linux Guest on Hyper-V -- no problems -runs perfectly but looking at the VM settings seems the "boot device" is a file with the name shim.efi. I'd have thought that the Guest would have booted from the appropriate boot file, grub2/systemd in Linux or the efi partition on Windows.

Any idea or is it just how Hyper-V names a "foreign" e.g non Windows boot manager file.

View attachment 112493

Cheers
jimbo

Click to expand...

Shim.efi will be the name of the .efi configuration file in the guest vm EFI partition.

Hyper-V is quite clever and uses that as the fastest way to boot bypassing boot managers (in effect).

Hyper-V does the same with Windows guests i.e. it points to a .efi file by default.

However, once in a while, it does not boot properly, so I change order to boot from hard drive instead and presumably the boot manager takes over.

cereberus said:

Shim.efi will be the name of the .efi configuration file in the guest vm EFI partition.

Hyper-V is quite clever and uses that as the fastest way to boot bypassing boot managers (in effect).

Hyper-V does the same with Windows guests i.e. it points to a .efi file by default.

However, once in a while, it does not boot properly, so I change order to boot from hard drive instead and presumably the boot manager takes over.

Click to expand...

Thanks
!!
I think you must be replacing karifor the moment. as the current resident Hyper-V guru.I hope he's still around somewhere.

Cheers
jimbo

jimbo45 said:

Thanks
!!
I think you must be replacing karifor the moment. as the current resident Hyper-V guru.I hope he's still around somewhere.

Cheers
jimbo

Click to expand...

He was last noted as logging in at end of September. So I guess he is still with us.

My fear is his illness has left him unable to easily type any more.

Re. being resident guru, I can only walk in @Kari's shadow as Grasshopper to the Master.

cereberus said:

He was last noted as logging in at end of September. So I guess he is still with us.

My fear is his illness has left him unable to easily type any more.

Re. being resident guru, I can only walk in @Kari's shadow as Grasshopper to the Master.

Click to expand...

Hi there
I'm working currently at the moment in finding out why latest version of (std- 24H2 non insider version) of Hyper-V seems to prevent communication FROM GUEST to HOST (but OK with communication TO GUEST from HOST) using exactly the same (not any change) in either HOST hardware), external switch and also with no any updates of any sort on the Guest (Linux) system. Even ping from GUEST to HOST doesn't work --gives me ping from lan.vmname xxx.xxx.xxx.xxx which is correct but then just freezes and anything like filezilla / ssh etc to host doesn't work either --but 100% the other way around. All OK on other computers on LAN -- so I suspect (as per usual) it's a Windows Networking problem.

On insider builds W11 build 26257.5000 - even though expiry date is 15 / sep is the last insider build I have and that works OK too -- I really don't though want to mess around with these insider builds unless I really have to.

I'll see what happens when updating this build though.

cheers
jimbo