sqlplus sys/oracle@server_name/orcl

SQL*Plus: Release 10.2.0.1.0 - Production on Fri Apr 12 11:07:15 2013

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ERROR:
ORA-12518: TNS:listener could not hand off client connection

Completed: alter database open
Thu Apr 04 17:06:19 2013
db_recovery_file_dest_size of 4096 MB is 0.00% used. This is a
user-specified limit on the amount of space that will be used by this
database for recovery-related files, and does not reflect the amount of
space available in the underlying filesystem or ASM diskgroup.
Thu Apr 04 17:35:11 2013
Incremental checkpoint up to RBA [0x3c9.847.0], current log tail at RBA [0x3c9.fe5.0]
Thu Apr 04 17:45:39 2013
Starting background process EMN0
EMN0 started with pid=20, OS id=1156
Thu Apr 04 17:45:39 2013
Shutting down instance: further logons disabled
Thu Apr 04 17:45:40 2013
Stopping background process CJQ0
Thu Apr 04 17:45:41 2013
Stopping background process QMNC
Thu Apr 04 17:45:42 2013
Stopping background process MMNL
Thu Apr 04 17:45:43 2013
Stopping background process MMON
Thu Apr 04 17:45:45 2013
Shutting down instance (immediate)
License high water mark = 4
Thu Apr 04 17:45:45 2013
Stopping Job queue slave processes
Thu Apr 04 17:45:45 2013
Job queue slave processes stopped
All dispatchers and shared servers shutdown
Thu Apr 04 17:45:52 2013
alter database close normal
Thu Apr 04 17:45:53 2013
SMON: disabling tx recovery
SMON: disabling cache recovery
Thu Apr 04 17:45:55 2013
Shutting down archive processes
Archiving is disabled
Archive process shutdown avoided: 0 active
Thread 1 closed at log sequence 969
Successful close of redo thread 1
Thu Apr 04 17:45:57 2013
Completed: alter database close normal
Thu Apr 04 17:45:57 2013
alter database dismount
Completed: alter database dismount
ARCH: Archival disabled due to shutdown: 1089
Shutting down archive processes
Archiving is disabled
Archive process shutdown avoided: 0 active
ARCH: Archival disabled due to shutdown: 1089
Shutting down archive processes
Archiving is disabled
Archive process shutdown avoided: 0 active

ORA-12560: TNS:protocol adapter error