Usually we can use below batch file to check domain controller schema version.

ECHO OFF

REM Change the line below. Example: SET domain=dc=mydomain,dc=com

SET domain=dc=exampledomain,dc=com

ECHO.
ECHO Finding Schema Level on Domain Controllers in domain %domain%..

SET file=schemainput.txt
dsquery server -o rdn > %file%
FOR /f %%a IN (%file%) DO CALL :Loop %%a
REM Cleaning up the temporary file.
IF EXIST %file% DEL %file%
GOTO :eof

:Loop
SET dc=%1
ECHO.
ECHO %dc%
dsquery * cn=schema,cn=configuration,%domain% -scope base -attr objectversion -s %dc%|FIND /i /v "objectversion"
GOTO :eof

Another very quick way to check this with only one command line is using the repadmin tool:

repadmin /showattr * “cn=schema,cn=configuration,dc=yourdomain,dc=com” /atts:ObjectVersio

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