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Automating IP addresses with TMG

In the past few months I've had the "opportunity" (note the quotes, maybe I'll write a post about all the troubles I've run into) to deal with some Office 365 integration projects.

When integrating one or more cloud services with Office 365 or Office 365 with on-prem Exchange, it is typical to limit the IP addresses that are aloud to communicate between services. This is an important layer on the security model and obviously reduces the attack surface. Microsoft maintains lists of IP addresses for the various services here:

http://onlinehelp.microsoft.com/en-us/office365-enterprises/hh373144.aspx

That page links to other pages with more specific information about various other Microsoft cloud services such as the link below for Exchange online.

http://help.outlook.com/en-us/140/gg263350.aspx for example.

At the time of this writing, you'll notice that the lists are inconsistent between pages. >:-(

Microsoft on two separate Premier Support Calls has told me…
Recent posts

LDAP and SAN Certificates

Hey everyone - I ran across an interesting problem with certificates and services. The problem was that I needed to see which certificate is being presented to the client on a non-HTTPS service; specifically - binding to LDAP over SSL (LDAPS). So the question is, how can you be sure what certificate is being presented?

Windows, so far as I've been able to find, does not offer any native help in this regard. Luckily there is a solution, but first let me give you a slightly longer description of the scenario so you can appreciate what we're talking about a little bit better.

An environment exists with some number of Domain Controllers, let's say ten. Within this environment, third party applications (think Java apps, Linux systems, etc) need to bind to LDAP to enumerate groups or validate authentication or whatever. These systems, however, can only have a single (or at best, two) LDAP hosts configured. What do you do? Pick two DCs? Round-Robin DNS?

Well, in my case, a load-b…

HomeDirectory name inconsistency and LDAP Query weirdness

Recently I was doing some work where I had to archive some home directories of people who were no longer associated with the company. A typical configuration looks something like this:


User:samAccountName  -> \\Server\Home\%username%

Such that the samAccountName property has the same name as the directory in whatever home share is being used.

What I ran up against, though, was that over the years - through marriages or divorces or other personal reasons, sometimes people would request that their username be changed. The company I was working with sometimes accommodates these requests. My job was to identify if any of the home folders were associated with accounts that had different names.

For example - consider this timeline:

1. User bjones is created with home directory \\Server\Home\bjones
2. bjones gets married and her account name is changed to bsmith

Now user bsmith has \\server\home\bjones for her home directory. This typically isn't a problem technically but administrativ…

Net User and Reset Password Delegation

Hey Folks - I ran into an interesting issue recently where a user who has been given the right to change the password for another domain user, could not do so.  Let me give you a bit of background.

I have a user (let's call him "Account Owner") who manages another account that is used to bind to Active Directory (over LDAPS). Let's call that account "Bind User".  So, Account Owner has the rights to change the password for Bind User.

I told the Account Owner that he could issue the following command to change the bind_user account password:

Net User Bind_User * /domain

I informed him that this command would prompt him for a new password and he could manage the account that way (so he didn't need to install any additional management tools). I told him that this should work from any computer to which he is currently logged on.  The problem, as it turns out, was that I was wrong.  But why?

To answer that question, I configured one of my labs so that I can re…

Get-Help vs Help - the paging/pager inconsistency

When I'm teaching PowerShell to folks, I often like to use the full name of the cmdlets - get-help instead of 'help', get-childitem instead of 'dir'. You get the idea.

I do this to help drive home the verb-noun syntax and because I can't necessarily expect everyone to know the shortcuts that I tend to use.

Well, the problem that I'm about to describe hasn't come up too much - but its annoying and I finally decided to take a minute and figure out what's going on.

The Problem (Powershell 2.0 or 3.0) In powershell, if I issue the command:
get-help <cmdlet> -full
then I get a wall of text that is not paged (where paging is that "-- More  --" at the bottom of the screen that allows me to read a page at a time.
To be honest, I'd never really spent more than a second thinking about this annoyance because it seemed so trivial, but since I'm in the midst of putting together a curriculum for a powershell class, it got a little more impo…

Windows Last Logon problem and solution

As someone who has been involved in Network Administration (in Microsoft Land) since Windows NT 4.0, I find it surprising that is still so difficult to get simple (yet important) information such as "When was the last time Joe User logged in?".

One would think that, with the fourth edition of Active Directory in production (Windows Server 2008 R2), a tool or set of tools would have been issued with Windows to provide those answers.  Well, because they don't, I've decided to go ahead and write one.  (Yes, I know that there are probably others out there to be downloaded or purchased but... you know, I don't care.)

All that is required: PowerShell 2.0 (and a functioning Active Directory).

Defining the Problem:
Active Directory stores numerous properties on objects in the Directory. Some of these properties are replicated amongst the Domain Controllers and some are not. Unfortunately, for some reason, one of the design decisions was to not replicate the "LastLogo…