There can be many reasons some of them listed below:
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1)bash-3.00$ cd $ORACLE_HOME/rdbms/lib
bash-3.00$ ls -altr config*
-rw-r----- 1 oracle oracle 260 Jul 6 23:27 config.c
-rw-r----- 1 oracle oracle 1216 Jul 6 23:52 config.o
bash-3.00$ cat config.c
/* SS_DBA_GRP defines the UNIX group ID for adminstrative access. */
/* Refer to the Installation and User's Guide for further information. */
#define SS_DBA_GRP "oracle"
#define SS_OPER_GRP "oraclei"
char *ss_dba_grp[] = {SS_DBA_GRP, SS_OPER_GRP};
Change: #define SS_DBA_GRP "oracle"
to: #define SS_DBA_GRP "dba"
mv config.o config.o.orig
make -f ins_rdbms.mk ioracle
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2)Improper relinking during installation
bash-3.00$ pwd
/d1/oracle/product/102/bin
bash-3.00$ ./adapters
Installed Oracle Net transport protocols are:
IPC
BEQ
TCP/IP
SSL
RAW
SDP/IB
Installed Oracle Net naming methods are:
Local Naming (tnsnames.ora)
Oracle Directory Naming
Oracle Host Naming
