12cR2静默建库，报错如下：  

[oracle@rhel6lhr dbs]$ dbca -silent -createDatabase -templateName General_Purpose.dbc -responseFile NO_VALUE \
> -gdbname lhr122  -sid lhr122 \
> -createAsContainerDatabase false \
> -sysPassword lhr -systemPassword lhr -serviceUserPassword lhr \
> -datafileDestination '/u04/oradata' -recoveryAreaDestination '/u04/flash_recovery_area' \
> -storageType FS \
> -characterset ZHS16GBK -nationalCharacterSet AL16UTF16 \
> -sampleSchema true \
> -memoryPercentage 10 \
> -databaseType OLTP  \
> -emConfiguration NONE
[WARNING] [DBT-14501] The version of the Oracle Grid Infrastructure for Standalone Server software is lower than database software version. Created database will not be registered with Oracle Grid Infrastructure.
   ACTION: Upgrade the version of the Grid Infrastructure software to register the database.
[FATAL] [DBT-10317] Specified SID Name (lhr122) already exists.
   ACTION: Specify a different SID Name that does not already exist.

 
解决：  
1、查看/etc/oratab中是否还有SID  
2、ps -ef|grep SID ，查看是否后台进程还有SID