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Monitoring social sites usage and sending warnings to users that went over daily quota
It is well-known how to block social network websites in /etc/hosts, squid, etc. But I don't want to block. I want to limit its usage and give all users in my company, let's say, 10 minutes per day to each such site or 30 minutes to group of sites like facebook, youtube, etc. Or, limit each user to one single visit to facebook.com per day.
Is squid configurable to do this? If so, how? What I need?