From Linux NFS
Special Note: This is alpha quality software based on draft standards. fedfs-utils-0.9 is not compatible with previous releases of fedfs-utils. Administrative protocols, commands, and data types stored in LDAP may change with the next release of fedfs-utils. This software is provided for testing only.
This series of articles will help you prepare for and set up a working FedFS domain using Linux and the fedfs-utils-0.9 package. The examples in these articles are not meant to provide an exhaustive description of all fedfs-utils features. They should provide coverage of common use cases and give you an idea of how to explore further.
fedfs-utils allows you to manage a FedFS domain, a single file namespace that consists of multiple filesystems residing on separate fileservers. A host can play one or more of these roles in a FedFS domain:
- File-access client
- This is a network file system client that communicates with fileservers using a standard file-access protocol (such as NFSv4).
- This is a server that stores data or refers file-access clients to other file-access servers.
- Namespace Database (NSDB)
- An NSDB node stores information about the location of filesets stored on file-access servers in a FedFS domain. LDAP is used to access and manage this information. An NSDB is optional. If an NSDB is employed, an administrative entity that has write access to FedFS records on the NSDB is required to create, modify and delete the entries that describe filesets residing in the FedFS domain.
- Administrative Client
- This is a network host where NSDB and FedFS ADMIN administrative tools are installed. These tools contact file servers and NSDBs to perform administrative tasks such as creating junctions.
A DNS SRV record refers file-access clients to the top-most directory in a FedFS domain, which is stored in a special export on a file server.
Building fedfs-utils 0.9
You must install fedfs-utils on each host that participates in a FedFS domain. Choose one of the following tasks:
- Installing fedfs-utils-0.9 on Fedora 19
- Installing fedfs-utils-0.9 on Enterprise Linux 6
- Building fedfs-utils-0.9
The remaining sections of the Installation Guide assume you have already performed any necessary fedfs-utils installation steps, except where noted.
Clients accessing an existing FedFS domain
If the storage servers in your environment already support a FedFS domain, it's easy to allow your Linux NFS client(s) to participate in the domain.
What you need for a minimal FedFS file-access client
If an NFSv4 client is to use Globally Useful Names (pathnames that appear the same on all FedFS clients), some additional set up is required. Here are the administrative steps that configure your Linux NFS client to participate in a FedFS domain.
Setting up a simple FedFS domain
Once you have FedFS-enabled clients, you can set up your own FedFS domain. A "simple" FedFS domain does not use a separate LDAP server to keep track of fileset locations. Only NFS basic junctions (which store fileset locations directly on file servers) are used.
What you need for a minimal FedFS file-access server
Any NFSv4 server can participate in a FedFS domain. However, an NFS server which will contain junctions must support new-style NFS referrals.
Use these steps when starting your own FedFS domain, or when adding a new Linux NFS server to an existing FedFS domain.
What you need to define a FedFS domain
Once you have prepared your NFS clients and servers, these steps create the FedFS name space and allow it to be discovered by FedFS-enabled clients.
- Setting up a FedFS domain root server
- Setting up a FedFS DNS SRV record
- Managing junctions with the nfsref command
Setting up a complete FedFS domain
A "complete" FedFS domain stores fileset location information in an LDAP server known as the domain's Namespace Database (or NSDB). Both NFS basic junctions and FedFS junctions can be used in this type of domain. A complete domain requires all the items in the "simple" FedFS domain set up above, and:
What you need for a minimal FedFS NSDB
To install and configured an LDAP server for use as an NSDB, choose one below:
What you need to administer your NSDB
NSDB administration tools must be installed and configured on at least one host.
- Setting up NSDB connection parameters
- Setting up NSDB administrative tools
- Distributing x.509 certificates for your NSDBs
What you need to allow file servers to access the NSDB
Along with the modified mountd and junction resolution library you installed above, fileservers that contain FedFS junctions also need to know how to contact their domain's NSDB.
What you need to administer junctions and NSDB connection parameters remotely
FedFS specifies an administrative network protocol that allows domain administrators to manage FedFS junctions and NSDB connection parameters remotely.
Installing this daemon is optional, since these operations can also be done by command line tools on the fileservers.
For fedfs-utils-0.9, running the administrative daemon on open networks is discouraged, since the daemon currently does not support any form of security. Future releases of fedfs-utils may include daemon support for RPCSEC GSSAPI flavors such as Kerberos.