[syslinux] Help with PXE "Out of Memory" error?

[Bruce Ferrell]

Gene,

I'm lurking on this issue. Just in general it's fascinating because I
basically use syslinux in a monkey-see-monkey do manner.

Can you explain why you used the menu entries that way?  What they actually do?

You mentioned logging... How is the enabled/configured?

Inquiring minds want to know and links to docs will do :)


On 10/03/2017 03:30 AM, Gene Cumm via Syslinux wrote:
> On Sun, Oct 1, 2017 at 8:00 PM, Locane via Syslinux <syslinux at zytor.com> wrote:
>> Hello all!  I have a server at work that we're using for PXE OS
>> installation and LiveCD loading.  It's based on CentOS 7.3, and CentOS
>> comes with Syslinux version 4.05.
> 
> Thanks for noting the version.  Are they the binaries from CentOS?
> 
>> We've been having this issue, very rarely, with some systems that refuse to
>> load a LiveCD from the menu, claiming they're "out of memory" when we know
>> that is absolutely not the case; there's plenty of RAM.  This video
>> <https://www.youtube.com/watch?v=y-rfNxA4VH0&feature=youtu.be> is of a
>> Supermicro H11DSU-iN motherboard throwing the error on LiveCD load.
> 
> It's partially true.  It's out of memory in the spot it attempted to
> load the files.  Are your logs verbose enough to see how much data of
> the initrd is actually transferred?  If not, have you attempted a
> packet capture to see how much is moved?
> 
>> To be clear, we've had literally thousands of diverse other systems and
>> servers run this LiveCD menu option with no issues; it's just this
>> motherboard and weirdly, any Celeron-based Intel NUCs - the NUC6CAYH.
> 
> It's all about how the underlying firmware sets things up.
> 
>> If no one has any ideas on why this might be happening, is there a guide or
>> tutorial on how to set up a newer version of the Syslinux PXE files under
>> CentOS 7.3?  I've been taking stabs at it by just replacing the 3 files
>> documented in the Syslinux PXELINUX wiki page
>> <http://www.syslinux.org/wiki/index.php?title=Install#PXELINUX>, but it's
>> behaving weirdly and, frankly, I'm kinda just taking stumbling around in
>> the dark here.
>>
>> Would appreciate some expert advice.
> 
> meminfo.c32 should give more insight.
> 
> linux.c32, although a lot less verbose during the loading of files,
> should be more intelligent in how it attempts to load files into
> memory.
> 
> LABEL livecd
>    MENU LABEL LiveCD_Unstable
>    LINUX /images/LiveCD_Unstable/unstable_vmlinuz
>    APPEND initrd=/images/LiveCD_Unstable/unstable_initrd.img my-options-here
> 
> LABEL livecd1
>    MENU LABEL LiveCD_Unstable1
>    COM32 linux.c32
>    APPEND /images/LiveCD_Unstable/unstable_vmlinuz
> initrd=/images/LiveCD_Unstable/unstable_initrd.img my-options-here
>