When installing Oracle 12c, on a Oracle Linux server, you can perform most of the prerequisites settings by using a cool script:
yum install
oracle-rdbms-server-12cR1-preinstall
Problem is that the script fails when started (really, was out of the box / freshly installed from Oracle repos):
oracle-rdbms-server-12cR1-preinstall-verify
/bin/sed: -e expression
#1, char 116: unknown command: `3'
/bin/sed: -e expression
#1, char 116: unknown command: `3'
cp /usr/bin/oracle-rdbms-server-12cR1-preinstall-verify
/usr/bin/oracle-rdbms-server-12cR1-preinstall-verify.bak
vi
/usr/bin/oracle-rdbms-server-12cR1-preinstall-verify
diff /usr/bin/oracle-rdbms-server-12cR1-preinstall-verify
/usr/bin/oracle-rdbms-server-12cR1-preinstall-verify.bak
< ${SED} -i /'^#[[:space:]]*$COMMENT'/d ${LIMITSFILE}
---
> ${SED} -i /"^#[[:space:]]*$COMMENT"/d ${LIMITSFILE}
570c570
< ${SED} -i /'^#[[:space:]]*$COMMENT'/d ${LIMITSFILE}
---
>
${SED} -i /"^#[[:space:]]*$COMMENT"/d ${LIMITSFILE}
Then you can use the script that saves you time for settings a lot of parameters needed for prerequisites.