The 411 on Private Lines
Published May 20 2019 03:10 PM 162 Views
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First published on TECHNET on Mar 11, 2011

A Snippets from the Shell article

By Christopher Wallick, BT

Hello once again from the chocolate factory. This week has been pretty interesting technically and I wanted to bring your attention to a little known (but very cool) feature of Lync Server 2010 Enterprise Voice: the private line. In Lync Server 2010 users enabled for Enterprise Voice can be assigned a secret secondary number known as the "private line."

The private line feature enables a user to have a secondary number which is hidden from the global address list and from other Lync clients. The intent of this feature is to be able to provision users with a number which can’t be easily found. And, as you might have guessed by now, private lines can only be provisioned using the Lync Server Management Shell by using a command like this one:

Set-CsUser UserAlias -PrivateLine "tel:+15555551234"

Note that that the private line bypasses most in-bound call routing rules; for example: a call placed to a private line will not be forwarded to a person's delegates.

An interesting fact about this feature is that once the private line property has been set on the user it doesn’t display as part of the default properties exposed using the Get-CsUser cmdlet. So then how do you whether the PrivateLine property is set or not? That’s a great question. One answer is that in Lync Server 2010 object properties have sub-properties. In order to display a user’s PrivateLine property you can assign the results of the Get-CsUser to a variable.

$user = Get-CsUser JoeUser

After that, you can return the PrivateLine property by exposing it from the variable.


Which when returned will present the number:


Setting the private line is actually the easy part. The interesting (and little-known) thing about private lines is that this feature is a pure Lync Server 2010 feature and is not supported or available to OCS 2007 R2 EV users. In fact the private line is not resolvable by any OCS 2007 R2 server. What this means is that, if you are in a migration state, calls placed to a private line number may fail if the OCS 2007 R2 mediation servers aren’t configured with a Lync Server 2010 pool (or Front End) as the next hop connection. Legacy OCS 2007 R2 servers are not capable of resolving the Private Line and as a result calls made to private lines will fail.

I know this article is a wee bit shorter than previous posts but I thought that, given the relative obscurity of the private line feature, it might be useful. As always. happy shelling and, remember: be careful out there.

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