NT 4.0 Service Pack 4: Advice for a Healthy System

On Oct. 21, 1998, Microsoft Corp. released Service Pack 4 (SP4) for NT Workstation and NT Server version 4.0. SP4 includes more than 650 new bug fixes, including 15 for year 2000 issues, repair for 28 memory leak conditions, several new features and all patches from SP1 through SP3.

Microsoft periodically packages hot fixes -- quick fixes for specific problems that are not regression tested -- into a cohesive service pack for the operating system. Microsoft has suggested that it could have sold SP4 as a point release upgrade, admitting that this service pack includes some serious changes. SP4 is the first service pack that addresses the NTS Option Pack and Enterprise Edition, but it is not intended for use with Microsoft Terminal Server Edition (TSE); a separate service pack for TSE will be released by the second quarter of 1999 -- a 0.7 probability. Microsoft states that all year 2000 fixes for NT TSE 4.0 will be available as hot fixes to the base TSE product.

SP4 Problems
Initial reports indicate many problems with SP4. Hardware original equipment manufacturers (OEMs) may not have drivers compatible with SP4 yet, causing problems with server video or disk drivers. Many OEMs provide their own plug-and-play and power management drivers for NT Workstation for their desktops and laptops, which are overlaid and disabled by SP4. Many application vendors have not yet tested and certified their applications for compatibility with SP4 and advise their customers to delay SP4 installation. Some users report that their servers were more stable under SP3, and there have been problems with Microsoft's own Exchange server. Unfortunately, due to year 2000 fixes in SP4, users may have no choice but to eventually install it.

Applying SP4
When applying SP4, enterprises should follow the same testing and upgrade procedures they use when deploying a point-release revision (see sidebar, Service Pack Application Best Practices), including performing a cost/benefit analysis and following well-defined change control procedures. Enterprises should check with their hardware and application vendors to ensure compatibility and fully test all systems in a lab environment before making the move. GartnerGroup estimates that it will cost an enterprise with 2,500 users, 33 file-and-print servers and 10 application servers running five different applications about $40,400 to apply this service pack to all servers and $114,700 to apply the service pack to every user machine. The project could take up to six months.

Enterprises that have already tested and certified their NT 4 servers as year 2000 compliant and applied SP3 and the year 2000 hot fixes should be aware that Microsoft has found more year 2000 issues in NT 4 and does not intend to make these fixes available as hot fixes for SP3 installations. Any further year 2000 problems that are discovered will be addressed with hot fixes for SP4.

Enterprises may decide to avoid installing SP4 by checking the list of year 2000 items fixed in SP4 and then deciding if they need SP4 to attain compliance. The risk here is that Microsoft does not intend to provide hot fixes for SP3 if more year 2000 issues are discovered in the future. Therefore, we expect that 80 percent of all enterprises will choose to take a "safe" year 2000 path and spend the time and money to upgrade to SP4 -- a 0.7 probability.

Recoverability Issues
There are several issues of recoverability with Microsoft service packs. While most of SP4 can be uninstalled, several specific patches and enhancements cannot. This means that a longer reinstall process would be needed to restore the system. Implementers should review the Microsoft documentation and take additional care when installing these patches and enhancements. Microsoft still needs to improve its service pack installation process.

After a service pack is applied, users must reapply the service pack every time they install new software or services from original NT CDs. This can extend downtime when installing additional features and cause extra downtime if technicians forget to reapply the service pack. Microsoft, however, will not offer CDs of NT 4 with the service pack preapplied, which would resolve this problem -- a 0.9 probability.

Bottom Line
SP4 for NT 4 is a major software upgrade and should be treated as such. Enterprises should not apply any NT service pack without first contacting all application and hardware vendors to ensure support by all relevant third-party product providers. Major service packs require testing and upgrade procedures similar to those that would be used when deploying a point release revision. Unfortunately, because Microsoft changed its position on year 2000 compliance, most enterprises will have no choice but to install SP4 by year-end 1999.

Service Pack Application Best Practices

  • Contact all third-party hardware and software vendors to ensure support and compatibility.
  • Test patches with as many hardware and software combinations as possible in a nonproduction lab environment.
  • Plan the service pack deployment as if it were a product point release: Coordinate process with business unit managers; schedule downtime and access to user machines at least one week in advance; arrange off-hours technical support during patch application; back up all production systems prior to patch installation; and have a contingency plan.