this check is not done when used switch ignoreSysPrereqs with runInstaller.
further you can help to ignore warnings but not errors.
Ignoring these errors may later need fixing same warnings.
So follow the check of prerequisite and install all necessary OS pacthes/RPMs or oracle supplied rpms OS patch.
below is how 10gR1 prerequisite or checked on RHEL 3 :
1.Checking operating system certification
Expected result: One of redhat-2.1,redhat-3,UnitedLinux-1.0
Actual Result: redhat-3
Check complete. The overall result of this check is: Passed
=======================================================================
Checking kernel parameters
Checking for VERSION=2.4.9.25; found VERSION=2.4.21. Passed
Checking for shmall=2097152; found shmall=2097152. Passed
Checking for shmseg=10; found shmseg=4096. Passed
Checking for semmsl=250; found semmsl=250. Passed
Checking for semmni=128; found semmni=128. Passed
Checking for filemax=65536; found filemax=65536. Passed
Checking for shmmni=4096; found shmmni=4096. Passed
Checking for semmns=32000; found semmns=32000. Passed
Checking for semopm=100; found semopm=100. Passed
Checking for shmmin=1; found shmmin=1. Passed
Checking for shmmax=2147483648; found shmmax=2147483648. Passed
Check complete. The overall result of this check is: Passed
=======================================================================
Checking recommended operating system packages
Checking for make-3.79; found make-3.79.1-17. Passed
Checking for binutils-2.11.90.0.8-12; found binutils-2.14.90.0.4-26. Passed
Checking for gcc-2.96; found gcc-3.2.3-20. Passed
Checking for openmotif-2.1.30-11; found openmotif-2.2.2-16. Passed
Check complete. The overall result of this check is: Passed
=======================================================================
Checking recommended glibc version
Expected result: 2.2.4.31.7
Actual Result: 2.3.2.95.3
Check complete. The overall result of this check is: Passed
=======================================================================
Validating ORACLE_BASE location (if set)
Check complete. The overall result of this check is: Passed
=======================================================================
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