Monthly Archives: July 2011

A Checklist for New Forms-Based Authentication Users in SharePoint 2010

Posted by Danny Jessee on July 23, 2011
SharePoint / No Comments

In recent weeks, I have done a fair amount of analysis and testing of various Claims-Based Identity scenarios in SharePoint 2010. One of these scenarios involves a web application configured to use Forms-Based Authentication (FBA obviously requires the use of Claims in SharePoint 2010) that is tied to a custom membership provider. The membership provider is quite simple, storing user IDs and passwords in a table within a SQL Server database (in plain text, so please don’t do this in production!) The solution was initially developed in MOSS 2007 and then migrated to SharePoint 2010. I have not yet performed a Visual Upgrade, which is why my screenshots still look “MOSS-y.”

There are numerous primers out there that explain how to handle the migration of existing FBA users to their Claims-based counterparts in SharePoint 2010, but what happens when you add new users to the custom membership database after the migration? Does everything go smoothly? In my experience, there are a few steps you should always perform to ensure all new users added to the membership database have the end-user experience you would expect.

First, I will create a new user and show you what may happen if you take no further action.

Step 1: Create the New User

This procedure will vary based on your custom membership provider. In this example, I will create the user example in my database table with an equally secure password (again, please don’t do this in production!)

What if I did nothing further at this point? Should the user example be able to log in to the FBA-protected site if he or she has not been explicitly granted any access (and when “All Authenticated Users” has not been granted any level of access to the site)? The answer may surprise you…

I’m in!

We’ll deal with this little bit of nonsense (the ugly Claims-encoded welcome name for the new user) in a minute. By the way, does anyone else find it amusing that the last two characters of the user’s display name are dropped in favor of a three character ellipsis (…)?

What’s even “better” is that example can click “View All Site Content” and navigate to all the lists and libraries within the site.

This does not seem like the behavior we would expect to see. How can we clean things up?

Step 2: Create an SPUser Object for the New User

In my initial quest to learn why a new FBA-user’s welcome name is always in Claims-encoded format, I stumbled upon Tyler Holmes’ excellent blog post entitled Awkward Usernames Courtesy of Claims Authentication (FBA). This led me to realize that I needed to update the DisplayName property of the SPUser object associated with the new user. Unfortunately, when I tried to run the PowerShell cmdlet Tyler provides, I found out that my new user doesn’t even have an associated SPUser object yet!


To create this object for my new FBA user, I run the following cmdlet:

New-SPUser -Web http://abc.shrpnt.loc -UserAlias “i:0#.f|abcmembershipprovider|example”


Before I run Tyler’s cmdlet to set the DisplayName for my SPUser to a friendlier value (although I now see example as the user’s name rather than its Claims-encoded equivalent), I thought I’d try logging in as example again to see if having an SPUser object for my new user makes a difference.

Access Denied?! But all I did was create a security principal (SPUser) for my new FBA user, I didn’t change any permissions…

Naturally this is the behavior one would expect to see when a new user is created and has not yet granted access to any resources. It’s a new FBA user (without a security principal)’s ability to have reader access across a site that has me more troubled.

Step 3: Grant the New User the Appropriate Level of Access

Unless you have assigned “All Authenticated Users” with a certain level of access to the site, you will experience the Access Denied error shown above. Just as in any other SharePoint deployment, a user with the appropriate level of access should assign the new user (either through a SharePoint group or directly) the permissions he or she will need on the site.

After this has been done, example is able to log in to the site once again. As an added bonus, example‘s welcome name at the top right of the page is no longer in Claims-encoded format.

Step 4: Set the New User’s DisplayName Value

When I created the user example in Step 1, I gave the user a name of Example User. I can run the following in PowerShell to set the user’s display name accordingly:

$user = Get-SPUser -Web http://abc.shrpnt.loc -Identity “i:0#.f|abcmembershipprovider|example”
$user.DisplayName = “Example User”
$user.Update()


This step is absolutely necessary if you do not use LDAP or BCS to map user profile properties to your custom membership provider’s data store. (Conversely, if you do use LDAP or BCS and have user profile synchronization configured, the value you set in this step will be overwritten the next time profile synchronization occurs.)

Now when example logs in, we see the new welcome name.

It’s worth noting that nothing within the infrastructure of Claims itself has anything to do with the user’s welcome name or how it is displayed. In fact, using the Claims Viewer Web Part, we can see that the information contained within example‘s Claim looks exactly the same as it did before example had an associated SPUser object. The display name we just set is not contained within the user’s Claim; it is only maintained within the SPUser object.

Conclusion

By following the above steps each time a new user is created, you guarantee consistency with each new user’s ability to access the site (and not have read access to all site content by default if this is not the desired behavior) and how the new user’s name is displayed. I strongly encourage you to automate this process using PowerShell or the object model if you need to create a lot of new users.

Have any questions, comments, or ideas you want to share? Feel free to post them in the comments below. If you will be at #SPSTCDC next month, feel free to come to my presentation on Claims-Based Identity at the August 11 meeting of the SharePoint User Group of Washington, DC. The meeting begins at 6:00 p.m.

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Which SharePoint Front End Server Am I Hitting?

Posted by Danny Jessee on July 03, 2011
SharePoint / 1 Comment

If you have ever worked in a network load balanced (NLB) environment with multiple SharePoint front end servers, you have no doubt had at least one occasion where only some of your users were seeing some sort of strange behavior. Perhaps some users receive a generic error message when accessing a page and others do not. Whatever the reason, it never hurts to be able to have users give you just a little bit more information to help you in the troubleshooting process.

Of course, you can always dig through the ULS log files on each front end server to look for any anomalies or to match up correlation ID values associated with generic error messages. But wouldn’t it be great if your end user could tell you that he or she is hitting front end #3 so you don’t have to waste time searching through the logs on front ends #1 and #2 first?

One potential solution to this problem (and there are no doubt more elegant ways to solve it) are to create multiple images such as the ones below:

Save each image with exactly the same name (such as frontend.jpg) and place it in the TEMPLATE\IMAGES directory of the SharePoint root on each front end (make sure you match up the correct image with each front end server!) Then, when something goes wrong for one user but not another, you can ask him/her to visit the following URL:

http://yourcompany.com/_layouts/images/frontend.jpg

Based on the number that appears, you will know exactly which front end that user is hitting!

I hope this information is useful to you. You could extend this by creating a custom URL action called “Front End Check” that allows certain users to hit the front end image link directly without having to remember it. Feel free to leave your thoughts and suggestions in the comments!

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