Farrah Abraham -- 'Backdoor Teen Mom' Porn Video Krushes Kim Kardashian Sex Tape

Farrah Abraham is a backdoor crowd pleaser for sure ... because there was such intense, pent-up interest in her porn video, it crashed Vivid's site.

According to our porn sources ... Farrah's 70-minute debut, "Backdoor Teen Mom," lured in more than 2 million visitors in just 12 hours Monday ... annihilating the record previously held by Kim K and Ray J -- which attracted 600,000 during the same time frame.

Farrah swamped Vivid's servers so hard ... the site went down Monday morning for 9 minutes ... which is more than enough time to satisfy most of the buyers -- trust us ...

Vivid honchos tell us they were able to access additional servers to handle, as they put it, "the immense load."

For the record ... Farrah also handled the immense load.