Unable to fetch tftp image: TFTP Error, start_image returned tftp error

[xutian]

When I boot my host from pxe server, pxe client download shim from tftp server successful, but shim failed to fetch netimage with error message like:

Unable to fetch tftp image: TFTP Error, start_image returned tftp error

[lcp]

Per UEFI SPEC, EFI_TFTP_ERROR from EFI_PXE_BASE_CODE_PROTOCOL.Mtftp() means "A TFTP error packet was received during the MTFTP session". Unfortunately, shim currently won't show the details of TFTP error code. According to RFC1350, the possible error codes are:

0 Not defined, see error message (if any).
1 File not found.
2 Access violation.
3 Disk full or allocation exceeded.
4 Illegal TFTP operation.
5 Unknown transfer ID.
6 File already exists.
7 No such user.

Maybe we can fetch the error code after getting EFI_TFTP_ERROR to help the user to identify the issue.

[lcp]

Could you try this patch and paste what it shows?
lcp@7a90c2a

[xutian]

@lcp
Thanks your patch and quick response, I will try on my host.
Thanks,
Xu

[daberkow]

I have been having issues for a while trying to get this to work, I may have an idea of your issue. The shim REQUIRES your DHCP server to be giving out "next-server" pointing to your TFTP host, if you are running proxyDHCP and dont have your primary server giving out a next-server address it will fail this way.

[AdamWill]

note for anyone else googling around forlornly: another possible cause of this is that shim always seems to want the grub executable to be in the TFTP root - even if shim itself is in a subdirectory. If it can't find the grub executable, you get this error.