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Hi, Bob Drake here again after a short blogging hiatus. I have put this two-part blog post together with hope that it will save you countless hours and a few aspirin when troubleshooting a slow logon. I have had the luxury of working many different slow logon cases and I have to say that these can be the most grueling to handle, depending on how they are approached and what information you have. There are multiple reasons why slow logons can occur and sometimes they are a result of multiple issues masked as one.
For this first part in the series I want to cover some well-known causes of slow logons, optimizing logon for your environment, and assist you with documenting your baseline to identify when you really have a slow logon issue. But before I do we need to set some expectations.
The “logon process” (I use this term to encompass both the boot up of the workstation and the user login that is completed with a functioning desktop) has a lot of moving parts. The most important question to address is “What is an acceptable logon time to you?” If you have expectations that your logon should only take 3-5 minutes from the time you turn your computer on to the point you get your desktop, you will have a brief window to perform all tasks. Your business requirements will dictate what you will be able to accomplish during the logon, so a thorough understanding of your goals is needed before moving forward.
Once you have your logon task list, then you can start testing the logon time frame. If all is configured and you are over your accepted limit, then an adjustment will need to be made by either limiting your tasks or accepting the lengthier time. There is a saturation point that will be reached when you try to accomplish too much in too little time.
So you want to know what the top items are that will definitely slow your logon process? Here’s a list of configurations that will have an impact on your logon time:
Note: This is really important to understand that when roaming profiles are implemented, group policy software installations and folder redirection requires that the user is NOT logged on before the network is initialized and processes policy synchronously- ONE AT A TIME. This is the default behavior and changing it could cause inconsistencies with your logon.
Note: If home folders are needed with roaming profiles there is a registry key tweak (SafeDllSearchMode) that can be added that will change the behavior. If you’re not sure that this is an issue in your environment, take a network trace at logon and see if DLL’s are being queried across the network to the home folder. There is also another tweak on the same page (StartRunNoHOMEPATH) that will assist with applications doing this behavior.
Before we get into troubleshooting a slow login we need to first identify what is a slow login and where is it slow. To be able to say a logon or boot up is slow you must know what a normal logon or boot time looks like in YOUR environment. With the above expectations the next step is to document the time a logon takes under normal conditions and under load (morning and afternoon rush hours). This should be done with all the different operating system builds in your environment (desktops, laptops, servers, XP, Vista, Win 7, 2003, 2008, 2008 R2) to have a standard baseline to work with.
Here is a short starter list of things to include in your baseline documentation:
Once you have a solid baseline of average times, then you will know right away when logon times increase and where to narrow your search for the culprit. With the above documentation in hand the issue will be resolved much quicker. Without the documentation you’re setting yourself up for hours of agony and a costly resolution.
Be sure to check out the next part in the series on slow logon where we actually get into the troubleshooting steps.
See you then…..
Click here for Part 2!
More reading here:
- Bob “My idea of a short hiatus is 18 months” Drake
If the logon is slow only when you are out of office, have a look at the following:
http://robsilver.org/ad/slow-logon-from-home-and-out-of-office/
Hope this helps,
Rob