Skype for Business 2019. Its kinda new AND old, when online cloud is considered. But the new way in which the web meetings app works is sometimes strange.
Ok, I can’t say I found ALL the answers in this particular puzzle, but I’ll give the ones I’ve found to you.
The scenario was that a customer had a Skype for Business (SfB) 2019 pool hosted and had an issue where people joining any meeting using the Skype Meetings Application. The problem they had was that anyone joining on the web would have to wait at least 40 seconds before any response.
Annoying, eh?
Some of you may say that ahhhh it was the connection from the Front Ends (FE) to the internet. AND you would be right!
SfB 2019 servers only offer the Skype Meetings Application AND this is only downloaded from Microsoft 365 or the Office 365 CDN. Check out meetings requirements here.
Mechanics of the process
The nuts and bolts are that the SfB server shares a web page (LwaClient.aspx). This code attempts to contact 365 endpoints *.microsoft.com, *.sfbassets.com and *.skype.com (just to name a few). This usually results in a twenty second delay and then timeout, if these are blocked at the internet corporate interface level.
So, the request goes out from the pool to the corporate network towards the internet. This gets blocked at the corporate internet end, and so the SfB 2019 pool request just times out.
There may be also a forty second timeout. When the LwaClient.aspx resolves 365 endpoints and then retrieves the configuration from the ECS (Experimentation and Configuration Service).
Fixing the timeout
BUT how do we fix this… there are three options:
- Just take the delay. Be brave and don’t use the meeting facility if you don’t have a “proper” full SfB client…
- IF there is internet access permitted from the SfB 2019 pool, specify the proxy in the configuration section of the web.config file of the LWA on the FEs (see more notes on this way below).
- IF internet access is not permitted on the SfB 2019 pool (where are you living in? the twenties?), then get the corporate firewall people to reject the connection straight away. This will respond back to the SfB pool and then you can carry on your merry way.
What about point number two above, you asked me to look further down the notes?
Ok then… The issue is that the endpoints on O365 require some “adjustment” to have the proxy specified.
Have a look here at the modern authentication prerequisites. Please note that these do refer to the O365 setup AND (at the date of the post of this article) do reference the SfB 2015 environment.
This is the explanation of the XML part of that “snip”.
The important part here, is to edit the two web.configs, on each of the FEs in the pool. Remembering that that the SfB server is 2019 in this example:
C:\Program Files\Skype for Business Server 2019\Web Components\LWA\Int\web.config
C:\Program Files\Skype for Business Server 2019\Web Components\LWA\Ext\web.config
And the point that is important, is to place the system.net section at the END of each of the files.
Good luck!
