I had a request to do a quick write up on how to configure extension mobility properly.
These are the steps involved (considering Call manager Linux versions):
1 – Configure extension mobility service by going into Device > Device settings > Phone Services
The service URL is : http://call-manager-IP:8080/emapp/EMAppServlet?device=#DEVICENAME#
If you want to set it up as an Enterprise service then check that box “Enterprise Subscription” otherwise leave it. If you check that box, extension mobility service will appear globally for all phones and you won’t be able to find this service under phone Subscribe services in Step 2. If you don’t check that box then move to step 2
2 – Under phone, susbcribe this service as follows by dropping down the menu at top right corner and then going into “Subscribe/Unsubscribe Service”
3- Staying on the same phone page, scroll down and check the extension mobility check box otherwise no one will be able to login:
4 – Create a User device profile Device > Device Settings > Device profile. Any higher generation phone profile will work on lower one but that’s not true the other way around. So a Cisco 7960 device profile can be used to login oo a 7912 phone but a Cisco 7912 UDP won’t login on a Cisco 7960 phone.
5 – After creating UDP, the most important and sometimes missed step is to subscribe the Extension mobility service again like step 2 at UDP level
6 – Go into user from from User management > End user and add that device profile to it. Also select the primary extension at that user page.
Login and you should be good to go. Any issues, it would either be related to service not subscribed at UDP level or a UDP not associated with a user.
Web Link for EM:
There can be a situation where your Pub is down or inaccessible and users wants to login or logout. As EM service is dependent on Publisher they won’t be able to login/logout and will get “host not found”.
There is a workaround where users can login to their phones through a web link.
To login using URL:
http://<CUCM-SUB IP Address>/emapp/EMAppServlet?device=MACADDR&userid=USERID&seq=XXXXX
XXXXX = Pin
Example:
http://192.168.70.11/emapp/EMAppServlet?device=SEP001E4AF0F9E4&userid=ajon&seq=12345
To logout the user:
http://< CUCM-SUB IP Address>/emapp/EMAppServlet?device=SEP001646D97913&doLogout=true
voiceonbits.com 
hi, great article,
but us there a way for a user to automatically logon to their phone?
i get a lot of calls from users they forget their PIN’s and are unable to logon, and then are not reachable by phone. this is costing us business if people cannot login.
any tips?
thank you in advance.
regards,
Henk
Hello, I don’t think so! you need pin to login to EM.
Only alternative I can think of is what we do here in my office ..we keep phones logged in..I know it’s not secure but that’s the way it is if people cannot remember their pins OR reset their pin from Call manager when someone forgets it.