Braving a tough public market, web-hosting company went public Friday with an initial public offeringn and is now trading on the New York Stock Exchange under the ticker symbol “RAX.”

[Among the investors in Rackspace is Raleigh-based Red Hat (NYSE: RHT).]

San Antonio, Texas-based Rackspace (which hosts VentureBeat), announced the IPO last night, selling 15 million shares priced at $12.50. That raises a total of around $187 million, less than half the $400 million the company had hoped for when filing to go public in April.

Still, any IPO at all is encouraging after a quarter without a single venture-backed IPO. Trading opened at $10 per share, rose to $11.58 and is currently at around $10.75.

Rackspace was founded in 1996 and raised around $30 million in funding. Backers include Norwest Venture Partners and Sequoia Capital, who owned 16.2 percent and 11.6 percent, respectively. Chairman and former chief executive Graham Weston owned 23.9 percent.

Rackspace says it has more than 33,000 customers worldwide, with $362 million in revenue last year.