[Discussion] OS Refresh after Hardware Upgrade

[Douglas Clark]

On Mon, 28 May 2007 09:11:09 -0600, Don Burch wrote:

>One of my IT tech guys always advocated reinstalling the last windows 
>service pack after making any hardware changes.
>
>Is there a similar strategy for OS2/ECS apart from a complete
>re installation?

Don,

Here is my two cents worth. There might be a reason to do this on Windows. There probably isn't a 
reason to do this with ECS.

On windows many hardware items come with drivers bundled with the hardware: scanners, 
cameras, etc. It is certainly possible for the driver that came with the hardware to be older than the 
corresponding driver installed in the latest Windows service pack - especially if the hardware is a 
little old and you have just installed a brand new service pack. So in this situation it probably 
makes sense to reinstall the service pack. However - this same reasoning also applies to software 
in Windows. Many software packages come with updated DLLs that contain "fixes" or 
enhancements that are not contained in the regular or older versions of the DLLs. It is very 
possible to install (older) software and have some of the system DLLs back-leveled to older 
versions than what is installed with a service pack. I believe that the newer versions of Windows 
have some utilities or "features" that attempt to prevent this from happening.

ECS doesn't usually have this problem for three reasons:

1) Most hardware drivers come from ECS/IBM/Serenity Systems, not the hardware manufacturers. 
Therefor there is very little chance that any hardware device is going to include a device driver, let 
alone one that has been updated by a service pack or later version of ECS.

2) To the best of my knowledge, IBM did not release special versions of DLLs to software (or 
hardware) vendors. All updated DLLs appears in service packs, so you didn't have to worry about 
DLLs in a software package overwriting DLLs in the x:\OS2\... directories.  The only exception I can 
think of off the top of my head is PMVIEW which includes a specific version of SOM.DLL that is 
installed to the x:\OS2... directories when PMVIEW is installed. However this version appears to be 
the same version that has been distributed with OS/2 for years and years. I almost always (when I 
remember) copy my existing SOM.DLL to a different name in case I need to recover after installing 
PMView, but have never had a problem.

However - I have seen situations where DLLs with the same name but different versions appeared 
in a system in different locations. Then the behavior of the system changed depending on the 
LIBPATH statement. If I remember right this was an issue with ODBC stuff and version 6 of DB2/2, 
and when installing IBM VisualAge C++ version 3 on ECS: the system would hang on reboot when 
finishing up the installation of VAC++ because of a LIBPATH statement that put some DLL 
(something with SOM I think) in front of the x:\OS2 path. Paul Curtis remembers the specifics of 
this problem - but if you rearrange the LIBPATH the install finishes OK and then it doesn't matter 
what the LIBPATH looks like.

But generally speaking this is not an issue with ECS.
Thanks

Douglas Clark