A months-long bidding war over Quest Software Inc. — a maker of data-protection and database-management software — appears to have reached its conclusion, with Dell Inc. announcing Monday that it has reached an agreement to buy Quest for $28 per share in cash in a transaction that values the Aliso Viejo-based company at roughly $2.4 billion.

In accepting Dell’s offer, Quest spurned a proposed $2 billion deal that would have seen venture capital firm Insight Venture Partners take the publicly traded company private. Quest has continued to solicit offers since the tentative deal with Insight was announced in March, and ultimately decided to take its business to Dell, which is looking to expand its recently created software group. (While the purchase price represents only a marginal premium over Quest’s $27.81 closing price Friday, the value of the company’s stock has jumped 43 percent since the day before the potential deal with Insight was announced.)