FreeBSD pxeboot unable to mount NFSroot

[vincenzo romero]

Hello all,

I would like to find out if the following is a known and documented
issue, and if so, can someone please point me to a link where I can
further understand the problem and cause.

I have encountered an issue where in a certain case a diskless client
is unable to mount NFSroot.  Here is the explanation:

PXE/DHCP/TFTP and NFS server - CentOS 5.1

- Multiple clients NFSroot mount exported on a per host basis.  One of
the clients is an NFS root mount image of FreeBSD 7

Configuration and Summary:
----------------------------------------

PXE/Server ---->  192.168.16.x network;  subnet:  255.255.240.0

Clients
-->  when clients are configured and defined in /etc/dhcpd.conf with
an assigned address in 192.168.16.x then it is able to boot
successfully - for all types of clients -(ie., FreeBSD and linux
flavors):
eg.:

host testclient1 {
  hardware ethernet 00:A0:DD:EF:5B:7E;
  fixed-address 192.168.16.39;
  filename "pxeboot";
  option root-path "192.168.16.5:/export/images/00A0DDEF5B7E/freebsd7_x64";
  option host-name "testclient1";

--> when we attempt to assign a FreeBSD client with an IP address
within the 192.168.17.x --- it is unable to mount its NFSroot export:

host testclient2{
  hardware ethernet 00:A0:DD:EF:57:CA;
  fixed-address 192.168.17.2;
  filename "pxeboot";
  option root-path "192.168.16.5:/export/images/00A0DDEF57CA/freebsd7_x64";
  option host-name "testclient2";
}

The clients' bootup process stops when attempting to mount the NFSroot
and drops into a "mount" prompt, forcing the user to enter a local
device to mount root.  Other linux flavor clients are able to boot
successfully, these clients use the pxelinux binary as opposed to
pxeboot that freeBSD clients use.

My question:  is there any known issue vis a vis the pxeboot
implementation so that it's unable to figure out that my 192.168.17.x
has a subnet of 255.255.240.0 and should be able to mount and "talk"
to its NFS server that is in 192.168.16.x?

Any advise would be greatly appreciated.

-- 
best,

Vince