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Installing patches 101

How to deal with patches

My last couple postings were about a bug fix for Windows, that I think is best avoided. Dealing with this particular fix, raised the issue, for me, of how to best deal with installing all patches, from a Defensive Computing standpoint.

I spent 10 years in the mainframe world administering to DB2 databases. The conundrum with installing patches is the same on mainframes as with PCs. Should you install every bug fix as soon as it's released or should you hold back a bit? And, if you do hold back, for how long?

The problem, in both environments, with installing bug fixes ASAP is that some will inevitably cause more problems than they fix. And when they do cause a problem, it may be a biggie, because a work-around could be days away. The problem with holding back, again in both environments, is how long to wait until you are reasonably sure that a patch won't break something accidentally. Do you install bug fixes a week after they were released? A month? Two months?

Mainframers have some advantage over Windows users when it comes to installing patches.*

For one, they can opt to not install patches until they "ripen" (my term). Assuming, for example, that patches are released monthly, a mainframe administrator can, if they want, install March patches in May and April patches in June. Windows/Microsoft update has no such date-oriented feature.

Another advantage is that mainframe patches are usually overseen by someone expert in the software being maintained. That is, a DB2 expert reviews the DB2 patches and can decide to omit some, if for example, they apply to features not being used. Likewise, patches for the operating system (z/OS) are typically reviewed by an expert in the OS before being applied. Needless to say, most PC users can not evaluate for themselves whether a particular patch is really needed or not.

Patching for non-techies

So, what should non-technical PC users do?

There is no one right answer. If non-techies install patches as soon as they are released, they are the least qualified to deal with problems caused by buggy patches. Yet, leaving their computers vulnerable to newly discovered bugs is risky too.

Many people recommend that non-techies let Windows automatically install patches as they are released. To recommend this is to trust Microsoft a bit more than I do. But, if the computer is used for non-essential things, and being without it for a period of time is no big deal, then installing patches automatically is the way to go. If the computer in question is used by children a lot, then again, installing patches immediately is probably the best approach.

But, some non-technical users make their living using a Windows computer, and they can't take the risk of a buggy patch causing a problem for which a fix may be days away. These people are probably better off waiting until a computer nerd can assist them, even if means being vulnerable to a newly discovered bug.

Patching For Techies

If you have the technical skill and the inclination, then I suggest turning off all the automatic processing offered by Windows/Microsoft Update. Don't even let it check for updates without downloading them. On top of this, I would also disable the underlying Automatic Updates Windows service (In XP, Control Panel -> Administrative Tools -> Services).

Once a month, I would enable and run Windows/Microsoft Update manually, then immediately disable it again.

When to run it? Installing patches a few days after Patch Tuesday gives Microsoft time to fix or withdraw any patches that caused widespread problems. Sometimes patches can be easily un-installed, but not always. Unless you make a disk image backup beforehand, I'd be very wary of installing patches on Patch Tuesday.

The classic trade-off has always been between security and convenience. Manually running Windows Update once a month is, admittedly, a nuisance.

To run a completely disabled instance of Windows/Microsoft Update in XP, you start by enabling the Automatic Updates service. This requires both setting it to start Automatically (note that it must be set to an "Automatic" startup, for some reason "Manual" is treated the same as disabled) and then manually starting it. Then run the update, selecting "Custom" rather than "Express" processing (see above). Before shutting down Windows, stop and disable the Automatic Updates service again. The Background Intelligent Transfer Service can be left at Manual startup at all times.

Disabling the Automatic Updates service has two added benefits. The minor one is that it enables XP to start up a bit faster.

The major one is that it also helps to protect you from Microsoft, which last September, forced updates on computers that were configured not to be automatically updated. I blogged about this at the time, see Windows is spyware and Defending yourself against Microsoft. I also recommend reading the September 13, 2007 edition of the Windows Secrets newsletter, specifically the lead article by Scott Dunn, Microsoft updates Windows without users' consent.

On a related note, as I wrote in April, Windows XP users should not be in a rush to install Service Pack 3. In fact, if someone suggested installing SP3 soon after it was released - don't take advice from them in the future. The problems that cropped up after its release were as predictable as the sun rising in the morning and the benefits are, by all accounts, minimal.

Patching Other Software

But what about the tons of other software, besides the operating system, that also needs to be patched?

In the Windows world this is a mess, if not a disgrace. Every software company re-invents the wheel when it comes to updating their software.

I'm not a Mac person, but I believe the situation is basically the same there, Apple's equivalent to Windows Update only updates Apple software. Linux has great potential in this area but I'm not familiar enough with it to judge if the potential is being realized. I do know that a number of Linux distros resisted my attempts to figure out how to update software. At least Windows Update is simple as easy to use, even in manual mode. Recently, a copy of gOS running a new computer totally refused to update anything and the error messages were of little help.

Macs and PCs will always be unreliable without a single patch delivery system for all the installed software.

In the meantime, some businesses make due with assorted commercial products that install patches to a wide range of software. A large computer company has home-grown software for doing this on the machines of employees. Home users have the Secunia Online Software Inspector; flawed though it is, you're much better off using it than avoiding it. FileHippo has a free update checker for Windows machines, but it is in beta test and requires .NET framework version 2. CNET offers VersionTracker, but it is not well rated by the 387 users that rated it.

In the long run this argues for Software as a Service, if for no other reason than, as in the mainframe world, experts oversee the patch process rather than normal, non-techie users. It may also lead to some type of virtualized desktop, again, motivated by the need to increase reliability by controlling software installations. Personally, I'm a huge fan of portable applications, that is, software that can run without being installed ( has a great collection). And while I'm not a big fan of software like GoBack to rollback system activity, it may justify itself by being able to undo any software installation, be it a patch or not.

Personal computing is a young field and the way patches are handled, shows all too clearly that this is still the Fred Flintstone era.

*NOTE: What Windows people refer to as a "patch" or "update", mainframe people refer to as a PTF - Program Temporary Fix.

See a summary of all my Defensive Computing postings.