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wimboot filename length restricted to 7 ? - Printable Version

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wimboot filename length restricted to 7 ? - cckp - 2014-09-11 03:32

hello all

good to know that latest wimboot (2.2.4) support UEFI booting.

but it seems that boot.wim filename max length is restricted to 7 ?

e.g.
if loaded with filename initrd 1234567.wim it's OK
if loaded with filename initrd 12345678.wim then boot failed


P.S. are these all same effect:
initrd boot/bcd bcd
initrd boot/bcd
initrd --name bcd boot/bcd
initrd -n bcd boot/bcd


RE: wimboot filename length restricted to 7 ? - cckp - 2014-09-16 15:41

ok , just found that maybe there're two types of name syntax.

1 , when booting in normal BIOS: initrd oldFilename newFilename
newFilename can be same as oldFilename, but must exist, not optional.

2 , when booting under UEFI : initrd --name newFilename oldFilename
newFilename is optional. can be shorted as: initrd oldFilename


RE: wimboot filename length restricted to 7 ? - mcb30 - 2014-09-16 16:38

(2014-09-11 03:32)cckp Wrote:  but it seems that boot.wim filename max length is restricted to 7 ?

e.g.
if loaded with filename initrd 1234567.wim it's OK
if loaded with filename initrd 12345678.wim then boot failed

There shouldn't be any 7-character limit. wimboot supports long file names (which is required for some of the other boot-related files, e.g. font files).

Quote:P.S. are these all same effect:
initrd boot/bcd bcd
initrd boot/bcd
initrd --name bcd boot/bcd
initrd -n bcd boot/bcd

No. As a general rule, use

Code:
initrd url://path/to/filename filename

i.e. ensure that the basename of the URL matches the filename you provide as the argument to "initrd". If you can't do this, then you can use

Code:
initrd -n filename url://path/to/anywhere filename

i.e. forcibly override the filename as seen by iPXE using the -n/--name option.

Michael


RE: wimboot filename length restricted to 7 ? - cckp - 2014-09-21 15:39

Quote:
There shouldn't be any 7-character limit. wimboot supports long file names

sure , it does support long file names

but my point is , the boot.wim file name, not font name

tried many times , modified bcd using bcdedit, set it to point to diffent length boot.wim flenames

I found that the filename length of the .wim file
can be shorter than 8, like 4,5,6,7 ,
and can be longer than 8, like 9, 10 , 11,
but , can NOT be 8.

e.g. in bcd you can set it to point to
\sources\boot.wim (default , length is 4)
\sources\boot5.wim ( length is 5)
\sources\boot56.wim ( length is 6)
\sources\boot567.wim ( length is 7)
-
\sources\boot56789.wim ( length is 9)
\sources\boot567890.wim ( length is 10)

all boot ok with wimboot 2.2.4(uefi and bios)

but you can NOT set .wim name in BCD like this:
\sources\boot5678.wim ( length is 8)

but older version wimboot can boot with .wim filename length 8
and MS can boot directly from PXE using bootx64.efi with .wim filename length 8


this is not a problem , since almost all the time the length is 4, like "boot.wim", and there's option for 5 6 7 9 10 ...

but why can not be 8? interesting


RE: wimboot filename length restricted to 7 ? - mcb30 - 2014-09-22 14:52

(2014-09-21 15:39)cckp Wrote:  I found that the filename length of the .wim file
can be shorter than 8, like 4,5,6,7 ,
and can be longer than 8, like 9, 10 , 11,
but , can NOT be 8.

Good catch. I have found the bug in the wimboot code, which affects all filenames of exactly 12 characters. Could you let me know your name and e-mail address (for the commit log message)?

Quote:but older version wimboot can boot with .wim filename length 8

This is unlikely; the code in question has been present since the first released version of wimboot (v0.9).

Michael


RE: wimboot filename length restricted to 7 ? - cckp - 2014-09-23 03:43

Sorry for the older version part.
If I tried some more tests, I may found the 12 character limitation by myself...
Anyway it's good to know that it help you to find out the real thing. feel honored , just reference me as a forum member.


RE: wimboot filename length restricted to 7 ? - mcb30 - 2014-09-23 16:03

(2014-09-23 03:43)cckp Wrote:  Sorry for the older version part.
If I tried some more tests, I may found the 12 character limitation by myself...
Anyway it's good to know that it help you to find out the real thing. feel honored , just reference me as a forum member.

Done; released as v2.2.5. Thanks for the bug report!

Michael