[syslinux] pxelinux 4.03 taking forever to find ..../pxelinux.cfg/default

[Gene Cumm]

On Tue, Nov 16, 2010 at 21:25, Jeffrey Hutzelman <jhutz at cmu.edu> wrote:
> --On Tuesday, November 16, 2010 09:19:02 PM -0500 Gene Cumm
> <gene.cumm at gmail.com> wrote:
>
>> It's an interesting idea but I didn't think PXE clients register with
>> DNS or present a hostname in the DHCP request.  I also don't know of
>> any TFTPD that would even think of trying to use a name service (DNS,
>> /etc/hosts, etc) to resolve an identity.  I think that if there was a
>> TFTPD that could do this (optionally or not), this feature should only
>> be reserved for PXE use on a more secured networks where you know the
>> identity of every host (ie complete /etc/hosts and /etc/ethers) and
>> not used on a more general purpose network.  (But why would you be
>> using PXE, an insecure protocol that trusts the network and could
>> compromise a machine, on a secured network?)
>
> I could see a TFTP server using DNS to reverse-resolve client addresses for
> logging purposes.  And in some environments (such as ours), the DHCP servers
> issue DNS updates for every host that boots.

OK, I could see that too.  Collecting such information would help to
consolidate that data in one location without having to examine
multiple systems to find the data you might want.  Although, it could
really slow things down if things like the DNS timeout, querying
multiple servers, and caching are not set appropriately.

I know that in my work environment, it appears DHCP updates DNS when
the DHCP client has selected a name (at least by the end).  It looks
like at least one of my PXE clients requests a hostname but my DHCP
servers don't bother handing one out.

-- 
-Gene