A recent HD failure and next year's first quarter release of Red Hat's
EL5 made me decide to temporarily use FC6 on my sandbox system, an IBM
Thinkpad T40. UDB 8.1 (FP14) and a UDB 9 Express-C were successfully
installed after resolving some problems. Fedora Core 4 is mentioned in
the UDB install documentation as a acceptable base for development
systems and it appears that FC6 will support running DB2.

1. Neither UDB version will install from CD. The #!/bin/sh command that
starts all of the scripts fails. This is caused by SELinux not allowing
execution of the scripts from the CD. Fix by using one of the following:
  A. Disable SELinux
  B. Put SELinux into permissive mode. (Log errors and ignore them.)
  C. Copy CD to a HD directory and install
I expect a future update from RH to the SELinux rules will fix this.

2. UDB 9 Java installation works with supplied Java. UDB 8.1 will not
install with Java. The Java included with the 8.1 UDB CD doesn't run
under FC6's 2.6.18-1 kernel. The UDB 8.1 control center will run under
IBM  Java2-150 and Sun Java 160. I've never been able to get UDB to
install using the DB2USELOCALJRE and JAVA_HOME environment variables
since, I think, Java 131. (The test program always returns a bad return
code.) Install (8.1) by:
  A. Use db2_install command. Install FP14 before creating the
     DAS or DB2 instances.

3. UDB's libimf.so (common code used by many other programs) crashes
before it starts running. This will show up first when db2fmcd     fails
and respawns fast enough for the kernel to diable it. (db2fmcd is
started by a line in /etc/inittab - usually the last line of the file.
The inittab entry is created when the first DB2 instance is created.)
Fix by using one of the following:
  A. Disable SELinux
  B. Put SELinux into permissive mode
Hopefully, IBM will resolve this by supplying an appropriate SELinux
policy statement with a future fixpak.

For my rebuild, I deleted the sqllib directories from all of the
instances (/home was undamaged), used root to reconstruct the ids and
groups manually specifying their id numbers to match the destroyed
system, then created new instances using db2icrt and dascrt. I then
issued a db2start command and recataloged all of the databases. FP14 was
higher than I'd previously had installed so I ran the rebinds that were
needed.

I hope that IBM does not delay approval of RHEL5 as a recommended
operating system for UDB.

Phil Sherman