Resolved SCCM 2012 R2 (extadsh) Schema Extension Error code 8224 and 8202

I used to support SMS 2003 and SCCM 2007 in my past experiances, Its been a past while and again I wanted to test SCCM 2012 in my Lab, while new installation of SCCM 2012 R2 (Extending Schema) I received below errors.

Failed to create attribute cn=MS-SMS-Site-Code. Error code = 8224.
Failed to create attribute cn=MS-SMS-Assignment-Site-Code. Error code = 8224.
Failed to create attribute cn=MS-SMS-Site-Boundaries. Error code = 8224.
Failed to create attribute cn=MS-SMS-Roaming-Boundaries. Error code = 8224.
Failed to create attribute cn=MS-SMS-Default-MP. Error code = 8224.
Failed to create attribute cn=MS-SMS-Device-Management-Point. Error code = 8224.
Failed to create attribute cn=MS-SMS-MP-Name. Error code = 8224.
Failed to create attribute cn=MS-SMS-MP-Address. Error code = 8224.
Failed to create attribute cn=MS-SMS-Health-State. Error code = 8224.
Failed to create attribute cn=MS-SMS-Source-Forest. Error code = 8224.
Failed to create attribute cn=MS-SMS-Ranged-IP-Low. Error code = 8224.
Failed to create attribute cn=MS-SMS-Ranged-IP-High. Error code = 8224.
Failed to create attribute cn=MS-SMS-Version. Error code = 8224.
Failed to create attribute cn=MS-SMS-Capabilites. Error code = 8224.
Failed to create class cn=MS-SMS-Management-Point. Error code = 8202.
Failed to create class cn=MS-SMS-Server-Locator-Point. Error code = 8202.
Failed to create class cn=MS-SMS-Site. Error code = 8202.
Failed to create class cn=MS-SMS-Roaming-Boundary-Range. Error code = 820.
Failed to extend the Active Directory Schema, Please find Details in "ExtADSch.log".

Other Errors Resolved
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After some dig down I found one of my Active Directory holding schema was down, I powered it on and tried extending schema again using extadsch.exe, But still got the same errors because  Replication out of sync between Active Directory. so i opened command prompt as administrator and run command "repadmin.exe /syncall".

You can also use GUI to start replication., Use Active Directory Sites and Services, go to your Site, under servers Select domain controller, collapse NTDS Settings, right click on <automatically generated> and select Replicate Now. and Wait for some time.

After extending schema I received message, Successfully extended the AD schema. for further more information you can check ExtADSch.log.