How to Identify OS or Oracle 64 bit or 32 bit on Unix

It is very common question which version of oracle I need to install. 32 bit or 64 bit? As a 64-bit operating system can support either a 32-bit database or a 64-bit database. A 32-bit operating system cannot support a 64-bit database. So, version identification
How to Identify OS or Oracle 64 bit or 32 bit on Unix
It is very common question which version of oracle I need to install. 32 bit or 64 bit? As a 64-bit operating system can support either a 32-bit database or a 64-bit database. A 32-bit operating system cannot support a 64-bit database. So, version identification of the OS is necessary prior to install oracle. The following procedure will hopefully help you.Check whether OS is 64 bit or 32 bit.-----------------------------------------On Solaris,SQL> !/usr/bin/isainfo -kv64-bit amd64 kernel modulesSQL> !/usr/bin/isainfo -v64-bit amd64 applicationscx16 mon sse3 pause sse2 sse fxsr mmx cmov amd_sysc cx8 tsc fpu32-bit i386 applicationscx16 mon sse3 pause sse2 sse fxsr mmx cmov sep cx8 tsc fpuThis output tells us that solaris operating systems allow co-existence of 32-bit and 64-bit files.On AIX,$ getconf -a grep KERN$ file /usr/lib/boot/unix*On Linux,On HP-UX,/usr/bin/ getconf KERNEL_BITS/usr/bin/file /stand/vmunixOn linux,$uname -aLinux debian 2.6.18-4-686 #1 SMP Wed May 9 23:03:12 UTC 2007 i686 GNU/LinuxIf the output is x86_64 then 64-bit and i686 or similar for 32-bit.On windows,Start>All Programs>accessories> System Tools>System Information>look for under System summary.Or start>run>dixdiag>Then check for WHQL digital signature.Determine of whether Oracle Software is 32 bit or 64 bit.--------------------------------------------------------------------------------Method 1:--------------Go to $ORACLE_HOME/bin and see.# cd $ORACLE_HOME/bin# file oracleoracle: ELF 64-bit LSB executable AMD64 Version 1, dynamically linked, not strippedHere it comes 64 bit and hence oracle software is 64 bit. If the output of the "file oracle" command does not say 64-bit explicitly then you are running 32-bit Oracle. If you had 32 bit oracle software installed then output will be like,oracle@sol:/db/oracle/bin$ file oracleoracle: setuid setgid ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), dynamically linked (uses shared libs), not strippedMethod 2:----------------------Log on to SQL*plus and see the banner.-bash-3.00$ sqlplus / as sysdbaSQL*Plus: Release 10.2.0.2.0 - Production on Thu May 15 02:50:37 2008Copyright (c) 1982, 2005, Oracle. All Rights Reserved.Connected to:Oracle Database 10g Enterprise Edition Release 10.2.0.2.0 - ProductionWith the Partitioning, OLAP and Data Mining optionsMethod 3:Query from v$version.-------------------------------------sys@THERAP> select * from v$version;BANNER----------------------------------------------------------------Oracle Database 10g Enterprise Edition Release 10.2.0.2.0 - ProdPL/SQL Release 10.2.0.2.0 - ProductionCORE 10.2.0.2.0 ProductionTNS for Solaris: Version 10.2.0.2.0 - ProductionNLSRTL Version 10.2.0.2.0 - ProductionMethod 4: Check for lib, lib32--------------------------------------1) $ORACLE_HOME/lib322) $ORACLE_HOME/lib If the two directories $ORACLE_HOME/lib32 and $ORACLE_HOME/lib are existing then it is 64 bit.If there is only an ORACLE_HOME/lib directory then it is 32 bit client.