Under the partnership, HP will bundle the Sun operating system on several of its ProLiant and blade server models. The companies also plan to work on future server models equipped with both Solaris and OpenSolaris.
Other operating systems offered in the ProLiant line include Windows Server and Linux systems.
HP senior vice president and general manager for blade system and Insight software Mark Potter said that much of the deal was sparked by demand from HP's customers.
"The combination of Solaris and HP ProLiant delivers superior performance, scalability and virtualisation capabilities on x86 servers," said Potter.
"Backed by industry-leading HP Technology Services, the agreement gives our joint customers complete confidence to grow their businesses while also controlling costs."
For Sun, the move was made to increase Solaris' exposure.
"The endorsement of Solaris on HP ProLiant dramatically expands the available market for Solaris on x86 servers, building on the largest installed-base of any commercial UNIX and Linux distribution," said Sun executive vice president of systems John Fowler.
"The growing demand and ecosystem around Solaris helps to further propel its adoption, along with breakthrough technologies like ZFS and DTrace, and outstanding operational economics and market-leading support for thousands of ISVs and applications."
The deal will make Sun an official OS partner for the ProLiant line, though HP noted that the partnership will not extend to its Integrity server line, where the company's own HP-UX system will remain the operating system of choice.
