For AIX, try perfagent.server which is part of Performance Aide for AIX, an 
additional cost for this lpp.  In particular perfagent.server's daemon xmservd 
has an extensive MIB with an associated filtd (filter daemon) wherein 
thresholds can be set for all variables and traps generated.

However, for general failures, I find installing NetView's trapgend and then 
making all PERM errors alertable in addition to some 55 other selected errors 
such as KERNEL PANIC, KERNEL DOUBLE PANIS, JFS_FILE_FRAGMENTED, etc. does a 
creditable job of catching 90% of all "typical" problems.  Recall that trapgend 
watches the AIX errorlog for all "alertable" messages and when they appear, 
generates a trap to NetView.