Security startup Tanium landed $90 million in funding from Andreessen Horowitz Sunday, which makes it the VC firm's second biggest investment. That values Tanium at $900 million, according to the Wall Street Journal, which first reported on the deal.

Tanium's technology works by collecting real-time data across an organization's network, which includes PCs, servers and any software installed on the network. From that accumulated data, the company said that IT managers should be able to pinpoint operational problems within the system and locate any malicious software that may be lurking about, thus thwarting security attacks before they occur.

Tanium's founders previously were involved with the security startup BigFix,Inc., which IBM bought out in 2010 for an undisclosed amount.

According to Tanium, its clientele includes Fortune 500 customers in the financial services, health care and technology industries. The Berkeley-based Tanium has 65 employees and was founded in 2007.

In addition to the funding, Andreessen Horowitz's Steven Sinofsky will join Tanium's board of directors.

Post and thumbnail images courtesy of Shutterstock user Sergey Nivens.