Appendix B. Gateway Protocol Support; Protocol Gateway Limitations; Supported Protocols; Access Control Lists - Dell DX6000 Deployment Manual

Dell DX Object Storage – File Gateway Deployment Guide
If the available space on the partition where the spool/cache directories reside gets too low, cached
files with the oldest access dates will be flushed until adequate space has been regained. If more than
80% of the available space for the configured partition is utilized, the least recently used cached files
are flushed until the cache is reduced by 10%. The evaluation of available space considers all usage for
the partition, not just CFS usage, and includes any reserved space you have explicitly dedicated for
other purposes. For this reason, best practice is to configure a dedicated partition for the CFS spool/
cache with a minimum of 10GB of available space.

Appendix B. Gateway Protocol Support

This appendix provides information that may be useful to the CFS Protocol Gateway server
administrator or implementer.

Protocol Gateway Limitations

The CFS Protocol Gateway administrator or implementer should note that the Dell DX Object Storage
cluster provides support for a metadata-rich set of attributes that may be used to describe binary
objects that are being stored. The use of file sharing protocols limits how these may be used since
attributes that are not known to the underlying network file system topography cannot be utilized.

Supported Protocols

CFS can be used with any file sharing technology however, Dell's development efforts to date have
focused primarily on SMB/CIFS and NFS. The focus of this deployment guide is upon specific support for
SMB/CIFS and NFS.

Access Control Lists

POSIX ACL (Access Control List) metadata will be mapped into the Dell DX Object Storage HTTP SCSP
metadata header content only if the underlying file system has been mounted with POSIX compliant
ACL support and with Extended Attributes (EAs) enabled.
Where the CFS protocol gateway is used to access the Dell DX Object Storage via the SMB/CIFS
protocols, Microsoft Windows NTFS and NTFS5 ACLs will be mapped to the nearest equivalent POSIX
ACLs, but this will be possible only where the underlying file system has been mounted with support for
POSIX ACLs and Extended Attributes.
It should be noted that the mapping of MS Windows NTFS ACLs will be affected not only by a closely
approximated mapping to POSIX ACLs, but additionally may be overridden by specific share
specification parameters that can be used to enforce access controls in such manner that even the MS
Windows network administrator cannot change or override them. Description of such controls is beyond
the scope of this document.

SMB/CIFS Protocol Support

The CFS SMB/CIFS server makes use of Samba version 3.4.7 (or later). This application fully implements
all documented SMB (Server Message Block) and Microsoft Windows CIFS (Common Internet File System)
protocols. Samba has a complete implementation of these protocols however, the behavior of Samba as
the SMB/CIFS server in a Microsoft Windows network environment is determined by settings in the
/etc/samba/smb.conf file. For example, Samba can be configured so that only certain SMB protocols
are supported by setting the value of the max protocol parameter.
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