There are a few methods plumbers use to unclog drains. Often, before attempting to clear the drain, a plumber may conduct a video inspection to assess the cause and location of the clog. Video cameras are inserted into the drain and provide real-time video footage of the pipe's interior, allowing the professionals to identify the most effective method for clearing the blockage.
Unclogging methods include snaking, rooter service, or hydrojetting. The specific technique to resolve the clog will depend on several factors, so consulting with a qualified plumber to assess your drain issues is always advised.