kmdb has replaced kadb as the standard “in situ” Solaris kernel debugger.
kmdb brings all the power and flexibility of mdb to live kernel debugging. kmdb supports the following:
Debugger commands (dcmds)
Debugger modules (dmods)
Access to kernel type data
Kernel execution control
For more information, see the kmdb(1) man page. For step-by-step instructions on using kmdb to troubleshoot a system, see How to Boot the System With the Kernel Debugger (kmdb) in System Administration Guide: Basic Administration and How to Boot a System With the Kernel Debugger in the GRUB Boot Environment (kmdb) in System Administration Guide: Basic Administration.