Unfortunately QC/ALM does not store the information on the time users are rejected due to lack of license. Only when the user is allowed access to the application then the Session_History table stores the information.
A general rule of thumb is to have one license for every 4-5 users.
So let’s assume that we have 80 to 100 users then 20 to 25 Full Licenses should be an ideal number. However, this means that only 20-25 people could concurrently login at any one time. As you might know that there will be no restriction in the number of users who have access to the Application.
Another item to ask your HP sales representative is about tolerance level. This is a feature that is negotiated with your contract and set within the Site Admin program. It allows for occasional overages without having to formally buy additional licenses. Let's say we have 100 licenses and have a tolerance level of 20% -- that means that we could have 120 users concurrently login (occasionally).
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