While launching the applications after successful gateway authentication from the browser and Citrix workspace app. users get error "Gateway authentication failed because VDA refused connection ".

To confirm whether the number of dynamic servers has exceeded the limit, used the following command on NetScaler:

nsconmsg -d statswt0 -d current -g curdynamic_serverinfo

Upon finding the value exceeded, Rebooted the affected node clearing the dynamic service count, resolving the issue.

Problem Cause

This issue occurs due to a known limitation in NetScaler related to dynamic service creation. When the number of dynamic servers exceeds the maximum threshold of 64,000, NetScaler is unable to establish new backend connections.

The root cause is that NetScaler is unable to create additional dynamic services once this limit is exceeded, leading to connection failures and application launch issues.