Hi All,

This is my current setup:

All Server are running Lync Server 2013.

Currently these are the things that are working and not working

• Internal Clients have no problem connecting be it Lync 2010 / Lync 2013 Clients
• Mobility Clients (Lync 2013 IOS App) have no problem connecting to the server *However i do get dropped whenever i send a message to another user (message gets sent through but i get disconnected after, have to sign out and sign in again after that) 
• External Clients (Lync 2013 Client) cannot connect to server. *However if i edit the host file of the PC to point lyncdiscover and lyncweb to the LyncEdge External IP and then manually configure the connectivity to SIP.DOMAIN.COM:443 (have to force it to use port 443) then after that i am able to connect to the server from the internet.
• https://lyncdiscover.domain.com/Autodiscover/AutodiscoverService.svc/root currently returns a http 406 error and displays a blank page instead of returning a xml file. However https://testconnectivity.microsoft.com/ reply me with all autodiscovery test as successful with no warnings or errors. (be it externally or internally it doesnt work)
• Currently Edge is using a Internal PKI Certificate for both internal and external (as we are pending purchase of UCC Cert) and the reverse proxy server is using a wildcard certificate from GoDaddy. 

My questions would be:

1. Is there a need to do mapping of port 80 to 8080 on the reverse proxy to front *cause currently it was deemed as not required as we are using https 
2. Is it ok to use just 1 VIP on the Front End Pool with 2 Unique FQDN mapped to the same VIP for Internal and External Service on the front end.
3. How can i get my External Client to work normally 
4. Would there be any complications due to using of different certificate for Edge and Reverse Proxy? OR is my current issues due to the fact im using an internal certificate on my edge? 

What Reverse Proxy is being used ?

Certificates used in the Reverse Proxy should be from 3rd party, for the testing ensure the certificate used in Reverse proxy and Edge their chain is present in the machine from which external user is trying to log in.

If you perform NSLOOKUP from the External machine, does it succeeds ?

Reverse Proxy used is a F5 Big IP Hardware

Yes the certificate used in the reverse proxy is from 3rd party (GoDaddy) 

NSLOOKUP does succeed.

I assume the certificates used in the Lync environment, its chain is present in F5.

Do you see any info in regards to automatic sign-in failing in the UCCAPI logs for the external client ? or if you can share the client logs......