We're having a problem with the PXE / DTS processes hanging on our server
(the server is running NW 6.5 SP3 with ZfD 6.5 SP1a installed). It will
work perfectly for a day or two, and then overnight, it will just hang.
The rest of the server will work fine, and we can bypass PXE to do imaging,
but PXE booting will refuse to work.

I ran zenpxe.nlm in debug mode, and just before PXE/DTS goes out to lunch,
we get the following in the sys:\zenworks\zenpxe.log (none of the other Zen
logs seem to indicate any errors):

Error: receiving data..
proxyGetPXEMenuState returned menuState = 0
proxyGetPXEMenuState returned ERROR 0xfffffb50
proxyGetPXEFilename returned workToDo = 0
proxyGetPXEFilename returned ERROR 0xfffffb50
pxeProxyInit Success
Error: receiving data..
Error: receiving data..

The errors will repeat a number of times, and after that, we cannot connect
to the transaction server. PXE clients will get their
DHCP/Subnet/Transaction Server/Gateway ips, but they'll all fail with
"Error: No response from transaction server". I've confirmed that the
transaction server is still running, and it listening on the correct ports
(as are the rest of the zen processes). Stopping and restarting the pxe
processes will not help, only a hard reboot will fix it (the server will
not go down cleanly after this happens).

I looked up the error number, and can only find reference to it being an an
NDPS error -- 0xFFFFFB50 NWDP OE NF OUT OF MEMORY (Possible Cause: The
server is out of available memory.) Does anyone know if this error code
also applies to a memory problem in Zenworks? It might fit our situation,
as the problem usually occurs just after all of our clients do a pxe boot,
but I'd like to be sure that it's not a deeper issue. Related to that,
does Novell have any maximum recommended concurrent PXE/DTS connections?
If we need to spread out our reboots, it would help to know how far we need
to spread them out.

If it helps, the server health history shows that the server had plenty of
memory each time this happens.

Thanks for your help!