Kerberos Constrained Delegation
Constrained delegation is a security feature that limits the Avere cluster‘s access to core filer resources. It restricts operations that come from the cluster’s domain to particular services on the back-end core filer.
Avere Systems recommends allowing the cluster to access the SMB/CIFS service only, since the cluster should only send file and directory operations to the core filer as SMB operations when CIFS ACLs are in use. This means that no NFS file or directory operations from the cluster’s domain are permitted against the core filer.
Constrained delegation is necessary when using SMB ACLs for NAS core filer access.
Constrained delegation is configured on the Active Directory server. You must specifically authorize each cluster vserver to access the core filer’s SMB protocol. Details are in the AD Administrator’s Guide, which is also available as Appendix E: Configuring Active Directory for Avere SMB. Read the section titled 2. Configure Kerberos Constrained Delegation for a step-by-step procedure.
Kerberos constrained delegation should be used for any NAS core filer that uses CIFS ACL security and is accessed by a vserver that has a CIFS ACL junction defined to that filesystem. Constrained delegation is unnecessary for SMB access to cloud core filers or for NAS core filers that use POSIX style security.