I’m not talking about having too many friends on Facebook, too many connections on LinkedIn or too many followers on Twitter. I’m talking about the real deal – too many watchers – that is too many people watching or subscribing to your presence information.
If you are very popular other Microsoft Lync 2010 users might see the message Maximum Followers Reached in the contact card, when they want to see your presence (shown below).
It all starts by a user subscribing to another users presence. In my case it is tu26 subscribing to tu27’s presence. The relevant parts of the outgoing SUBSCRIBE is shown below with the 5 different categories being asked for.
CSeq: 1 SUBSCRIBE
<batchSub xmlns="http://schemas.microsoft.com/2006/01/sip/batch-subscribe" uri="sip:firstname.lastname@example.org" name="">
<action name="subscribe" id="94941760"><adhocList><resource uri="sip:email@example.com"/></adhocList>
On the Microsoft Lync 2010 Server the User Services component realize tu27 has reached the maximum and it returns the message below as a response to the SUBSCRIBE above.
CSeq: 1 SUBSCRIBE
<list xmlns="urn:ietf:params:xml:ns:rlmi" uri="sip:firstname.lastname@example.org" version="0" fullState="false">
<instance id="0" state="terminated" reason="quotaExceeded" statusCode="413" email@example.com msDiagCode="2012"/>
The msDiagCode = 2012 and statusCode = 413 are translated by the Microsoft Lync 2010 client into the message Maximum Followers Reached. At the same time the User Services component logs a warning with event id 32078 describing that the user has reached the limit (see below).
The net effect is that the user tu26 will not be able to see the presence of tu27 before one of the other watchers removes his subscription by signing out or removing tu27 from the contact list.
How can you as an administrator change the limit for these popular users?
In Lync Server 2010 the CsPresencePolicy controls the limit. It has two parameters MaxPromptedSubscriber and MaxCategorySubscription. The meaning of Prompted and Category Subscriptions are explained here. The default value for MaxPromptedSubscriber is 200 and the default value for MaxCategorySubscription is 1000 (the relationship 1:5 make sense since, as you can see above, presence subscription asks for 5 categories).
You can change the Global CsPresencePolicy, create one with Site scope or define one with user scope (tag) and grant the policy to the popular user.