Finding Out Which Lync Pool Servers a User is Associated With, and the Preferred Connection Order

We can find out which servers the user is associated with and the preferred order that the client will connect using the following in the Lync Management Shell:

Get-CsUserPoolInfo -Identity 'sip:testuser01@mylab.local' | Select-Object -ExpandProperty PrimaryPoolMachinesInPreferredOrder | Format-List MachineId,Fqdn

Error opening file for writing wireshark

During the installation of Wire Shark received below error

Click Abort to stop the installation,

Retry to try again, or

Ignore to skip this file.
---------------------------
Abort Retry Ignore 

To resolve the issue, You need to Install the Wire Shark by Run As Administrator. Using this you will be able to successfully install the Wire Shark in your machine to capture the network packets.

Lync Users from child domain are unable to communicate with Federated users

Issue: Internal users are unable to communicate with federated partners

Both parties use Open Federation. So, I have checked the UCCAPI logs after reproducing the issue.

Below is log reference

02/02/2014|20:28:56.359 D14:218 INFO  :: Data Received - *.*.*.*:5061 (To Local Address: *.*.*.*:63616) 765 bytes:

02/02/2014|20:28:56.359 D14:218 INFO  :: SIP/2.0 500 The server encountered an unexpected internal error

Proxy-Authentication-Info: Kerberos qop="auth", opaque="B65AC651", srand="38DAC634", snum="19", rspauth="040401ffffffffff0000000000000000d56cb1294aaddd51faf2098f", targetname="sip/*.domain.com", realm="SIP Communications Service", version=4

From: "TestUser"<sip:TestUser@Childdomain.com>;tag=e5eb8b9937;epid=9d9ec06d9b

To: <sip:FederatedUser@hp.com>;tag=07BCF4D13256B81D79E9A68DC93E4672

Call-ID: e8cdcc10ae654253a16910ec43813f5e

CSeq: 1 SUBSCRIBE

Via: SIP/2.0/TLS 10.160.8.134:63616;ms-received-port=63616;ms-received-cid=18C1F00

ms-diagnostics: 1008;reason="Unable to resolve DNS SRV record";domain="Child Domain.com";source="sip.domain.com"

Server: RTC/4.0

Content-Length: 0

02/02/2014|20:28:56.359 D14:218 INFO  :: End of Data Received - *.*.*.*:5061 (To Local Address: *.*.*.*:63616) 765 bytes

To resolve the issue CNAME & SRV record should be created

CNAME record to be created for Childdomain.com, Value: AccessEdgeFQDN

Federation record to be created in Public DNS

_sipfederationtls._tcp.childdomain.com 86400 IN SRV 0 0 5061 sip.childdomain.com

How do i know to which Front End Server my Lync Client registered

If you have multiple Front End Servers, your account will be randomly homed to one of them. Use the below command to retrieve the list of servers in order that a user will attempt to try to login

Get-CsUserPoolInfo -Identity 'sip:Firstname.Lastname@domain.com' | Select-Object -ExpandProperty PrimaryPoolMachinesInPreferredOrder | Format-List MachineId,Fqdn

Lync Server uses a hash algorithm to determine which front end server the client will primarily connect to, and also the order of failover for every front end server in the pool. This will ensure that all clients from the same user will consistently connect to the same front end server and in turn connect to the same registration database. The hash algorithm is based on the maximum number of servers in the pool (10). This will help ensure that users are evenly spread across all available front end servers in a pool. The maximum number of servers is used to ensure that hash values never need to be recomputed with the addition or removal of servers to or from the pool.

Refer: DNS Load Balancing