NetScaler Lync 2013 Frontend (Reverse proxy) balancing

I will not go into much detail about Lync 2013 infrastructures its just a basic setup to use the NetScaler as reverse proxy for external access to the Lync Frontend server. I am still working on the virtual server configuration for the Lync Edge and internal Lync Frontend server but will follow soon. Especially the Lync Edge is a bit tricky because you can’t use SNAT (not recommended) for your load balancing configuration, so the NetScaler needs to own the gateway and all traffic must path though the NetScaler.

Very useful is the Lync 2013 Protocol Map to understand the communication flow.

Add Custom Availability Monitors

add lb monitor monitor-LYNC-TCP4443 TCP -LRTM ENABLED -destPort 4443 -secure YES 
add lb monitor monitor-LYNC-TCP8080 TCP -LRTM ENABLED -destPort 8080

Add Lync Servers

add server LYFE01
add server LYFE02

Create Service Groups and bind Monitors

add serviceGroup service-LYNC-FE_8080 HTTP -maxClient 0 -maxReq 0 -cip DISABLED -usip NO -useproxyport YES -cltTimeout 180 -svrTimeout 360 -CKA NO -TCPB NO -CMP YES -appflowLog DISABLED 
add serviceGroup service-LYNC-FE_4443 SSL -maxClient 0 -maxReq 0 -cip DISABLED -usip NO -useproxyport YES -cltTimeout 180 -svrTimeout 360 -CKA NO -TCPB NO -CMP YES -appflowLog DISABLED

bind serviceGroup service-LYNC-FE_8080 LYFE01 8080 -CustomServerID "\"None\"" 
bind serviceGroup service-LYNC-FE_8080 LYFE02 8080 -CustomServerID "\"None\"" 
bind serviceGroup service-LYNC-FE_8080 -monitorName monitor-LYNC-TCP8080 
bind serviceGroup service-LYNC-FE_4443 LYFE01 4443 -CustomServerID "\"None\"" 
bind serviceGroup service-LYNC-FE_4443 LYFE02 4443 -CustomServerID "\"None\"" 
bind serviceGroup service-LYNC-FE_4443 -monitorName monitor-LYNC-TCP4443

Create Virtual Servers for Lync

add lb vserver vserver-LYNC-FE_80 HTTP 80 -persistenceType COOKIEINSERT -timeout 180 -cookieName MS-WSMAN -cltTimeout 180 
add lb vserver vserver-LYNC-FE_443 SSL 443 -persistenceType COOKIEINSERT -timeout 180 -cookieName MS-WSMAN -cltTimeout 180

Bind Virtual Servers to Service Groups and configure SSL

bind lb vserver vserver-LYNC-FE_80 service-LYNC-FE_8080 
bind lb vserver vserver-LYNC-FE_443 service-LYNC-FE_4443 

set ssl vserver vserver-LYNC-FE_443 -tls11 DISABLED -tls12 DISABLED 
bind ssl vserver vserver-LYNC-FE_443 -certkeyName

If you want more details please have a look into the Deplyment Guide – Citrix NetScaler for Microsoft Lync

More information about from Microsoft you find here: Network Planning, Monitoring, and Troubleshooting with Lync Server


F5 Load Balancer

My company decided to buy two F5 Big IP Local Traffic Manager 8950 for our web cluster systems with a maximum balanced capacity of 20 gigabit. We also got the F5 Local Traffic Manager as Virtual Edition for our test enviroment and to integrate it into the test network.

In the beginning the F5 looked very complicated but after some time now playing around with it and setting up things, it got easier and easier. I only need to have a deeper look at the iRules because this feature allows you can to really do everything with the F5 load balancer.

So for now I can’t really write more about it but I will soon ┬ápost some updates.

Next week I have the integration of the F5 Big-IP into the production network of my company and will start setting up the first new linux web cluster but only with a layer 4 balancing.


Here a nice picture of the new F5 BigIP boxes in the data center from my company:

For the new web cluster for my company we set-up layer 4 balanced web server pools and layer 7 balanced pools.

The layer 7 balancing was necessary because there where different server pools with applications that needed to run under the same domain and where routed on the expected http/https request. I will post the iRule for everybody soon.

Here two interesting ressources to get information:

Ask F5

F5 Devcentral