Listener:handler(s) for service

Question

Hello gurus,
When I do lsnrctl status it shows me,
Service "mtg01" has 1 instance(s).
Instance "mtg01", status READY, has 2 handler(s) for this service...
what is handler here and how no of handlers are being decided?
Thanks.
P

Answer 1

Gee, I think that's a fairly unhelpful response. The index for the 10g Net Services Guide contains no entry for 'handler'. How is the OP supposed to figure this out. I feel this is a legitimate question.
The part of the 10g docs to read is:
http://download.oracle.com/docs/cd/B19306_01/network.102/b14212/concepts.htm#i1051710
Even with that documentation it is hard to figure out that:
- A handler can be either a SID or service (like an oracle database service) that registers with the listener either by default (SID registers to localhost:1521), or explicitly by setting SERVICE_NAMES and/or LOCAL_LISTENER and/or DISPATCHERS (if Shared Server mode) to register a partocular database as a service on a particular listener.
- A handler can also be created by manually specifying static service registration in the listener.ora:
http://download.oracle.com/docs/cd/B19306_01/network.102/b14213/listener.htm#sthref793
There. Now isn't that a little more helpful and a little less self-righteous?
Regards,
Jeremiah Wilton
ORA-600 Consulting
http://www.ora-600.net