A Windows update that could be released today will break HP-UX PA-RISC monitoring in System Center Operations Manager. The update basically blocks the use of RSA keys less than 1024 bits in length, which will have an adverse affect on monitoring these UNIX systems.
No other UNIX/Linux monitoring will be affected, only HP-UX PA-RISC systems managed by Operations Manager will be affected.
For more detailed information on this update, and for resolutions, visit, http://blogs.technet.com/b/momteam/archive/2012/08/01/important-hp-ux-pa-risc-computers-monitored-by-operations-manager-will-experience-heartbeat-and-monitoring-failures-after-an-upcoming-windows-update.aspx.
If any more information is released, like details of the actual update that causes this problem, I’ll let you know.