If you create a System Management Container in AD and now you need to put the permissions this is the process to follow.
To apply permissions to the System Management container by using the Active Directory Users and Computers administrative tool
Click Start, click Run, and then enter dsa.msc to open the Active Directory Users and Computers administrative tool.
Click View, and then click Advanced Features.
Expand the System container.
Right-click System Management, and then click Properties.
In the System Management Properties dialog box, click the Security tab.
Click Add to add the site server computer account and grant the account Full Control permissions.
Click Advanced, select the site server’s computer account, and then click Edit.
In the Apply onto list, select This object and all child objects.