Solaris

Need inputs when physical server is coming down (ex- init 0) .

We have a physical server in that there are couple of LDOM's and in LDOM's there are couple of Zones . In zones there are applications running .

Physical Server (T4 Server) -> LDOM -> ZONES -> applications

There are scripts that has stop/start applications in zones when zones get rebooted .

So in the main Physical server when you use init 0 command . Does it bring down zones first and then LDOM's . What is the process . Please advice.

I would advise againt using init 0 on physical hardware before your have stopped all your LDOM(s) via ldm stop or init 0 (or 5) inside the LDOM.
This goes against documented practice for Oracle VM server.

If you issue ldm stop <domain>, it will send a shutdown signal to LDOM (in you case also a global zone), global zone / ldom sends a shutdown signal to zones.
It will stop all the services and daemons properly and umount the filesystems.
A clean shutdown of LDOM and zones inside will be made.

Question is why would you want to issue init 0 or init 5 on hypervisor, before stopping the domains ?

Hope the helps
Regards
Peasant