49ers defensive coordinator DeMeco Ryans is the new head coach of the Houston Texans.  Reports say it is a six-year contract for Ryans, who played linebacker for the Texans in six of his ten NFL seasons.  San Francisco has already requested to interview Commanders defensive backs coach Chris Harris for the open DC position, according to reports.  The Niners also requested to interview Panthers interim head coach Steve Wilks.  There are also reports San Francisco could pursue former defensive coordinator Vic Fangio, who coached with the team from 2011-to-2014.