NetWare 6.0 SP4/5 and 6.5 SP2 have been experiencing some pretty serious memory fragmentation problems with systems over 1 Gb of physical RAM. Check out this article over at support.novell.com TID10091980
In my experience, the abend that is caused by this error halts the processor and leaves the server console with just red and blue text.
There are a few questions to ask yourself about your server:
1. What other apps are running on it? NetStorage, Webaccess, iManager, etc.?
2. Are you using SSL anywhere?
3. How long has it been running without a restart?
4. Are you using NSS volumes or Traditional?
The devloper forums are one of my favorites, you can find those here.
There are updated Apache2 nlm's still in beta. They are version 2.0.52 and can be found here
Regarding the conversion to linux, Novell already has plans for you. Open Enterprise Server is scheduled to be released by the end of the year. It will bring feature parity between Novell's SUSE offerings and NetWare OSes. If you are an MLA/SLA customer you already have access to the SLES 9 Enterprise Stuff. More information on OES can be found here
. Most Novell products have long been available on Linux and are all pretty stable.
I have been using moodle on NetWare 6.5 SP2 and SLES 9 for awhile now myself. My 6.5 Sp2 box requires a restart every other week.
As someone who has been an ex-MSCE, Novell/Linux fan for almost two years now; I choose to stay out of the NetWare vs. Linux battle. All I will say is that Novell has done a great job of using software from the Open Source community.
I hope this helps,