Algorithm for usage of VCS 2011+ on CentOS 6.0+

kaluoota

Algorithm for usage of VCS 2011+ on CentOS 6.0+ =>
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1. In "/etc/redhat-release"  being "root / sudo(if applicable)" ==>
    -> Comment the existing version using "#" character in the above file [without quotes]
    -> Enter the following : "CentOS release 5.7 (Final)" <- Without quotes as the very "First Line"
    -> Save and exit as root (NO re-boot is required)
    -> Start using the VCS 2011+ assuming proper license is available for that machine / (over)network
2. After sims complete, either being bored of VCS(or Synopsys in general) or job complete =>
    -> Replace the original CentOS version line in the above file as the very "First Line"
    -> Retain the CentOS release 5.7 (Final) line, but commented using "#" character and as second(2nd)
         line without quotes as well
    -> Save and exit as root (or sudo if applicable)
3. Use CentOS normally as usual
4. Don't ever "upgrade/update/install" anything in the present OS(6.0+) when above file has Centos 5.7[+/-]
     as entry, otherwise even the kernel will get overwritten if updated while having 5.7 as entry even
     through the OS might be 6.0+
5. If Kernel of Centos 6.0+ is overwritten with kernel of Centos 5.7+, NO issues : =>
    -> Using YUM,  "re-install" kernel to come back to Centos 6.0+(6.1/6.2/6.x) and reboot
    -> All is well :-D
6. Take extreme care of => "/etc/redhat-release" file in RHEL/CentOS environment !!!
7. Even RHEL engineers can use the above algorithm because => CentOS is a carbon copy of => RHEL
8. Always have the right CentOS/RHEL version of the OS in the => "/etc/redhat-release" file for any other work
9. Always use YUM to re-install the necessary software to come back to the original version
10. Editing => "/etc/redhat-release" file : before and after use of Synopsys TOOLS(VCS etc....) w.r.t the right OS version
      without "upgrade/update/install/re-install" will save us from "head-ache, dandruff and hair-fall" :-)