RAC

Check All configured nodes in a RAC

  $CRS_ORACLE_HOME/bin/lsnodes -n

Check network interfaces configured 

$ORACLE_HOME/bin/oifcfg getif

Check Instance’s and there status 

column host_name format a30
select INST_ID,INSTANCE_NAME,HOST_NAME,STATUS from gv$instance;

Displays information on all database sessions for whole RAC.
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SET LINESIZE 500
SET PAGESIZE 1000

COLUMN username FORMAT A15
COLUMN machine FORMAT A25
COLUMN logon_time FORMAT A20

SELECT NVL(s.username, '(oracle)') AS username,
s.inst_id,
s.osuser,
s.sid,
s.serial#,
p.spid,
s.lockwait,
s.status,
s.module,
s.machine,
s.program,
TO_CHAR(s.logon_Time,'DD-MON-YYYY HH24:MI:SS') AS logon_time
FROM gv$session s,
gv$process p
WHERE s.paddr = p.addr
AND s.inst_id = p.inst_id
ORDER BY s.username, s.osuser;

SET PAGESIZE 14
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