Figure 9. The NFS Server

 

NFS is similar to other RPC-based services in its use of server-side daemons to

 

process incoming requests. NFS may also use multiple copies of some daemons to

 

improve overall performance and efficiency.

 

RPC Binder Daemon (RPCD)

This daemon is analogous to the port mapper daemon, which many

implementations of NFS use in UNIX. Clients determine the port of a speci®ed RPC

service by using the RPC Binder Daemon. Local services register themselves with

the local RPC binder daemon (port mapper) when initializing. On AS/400, you can

register your own RPC programs with the RPC binder daemon.

 

NFS Server Daemons (NFSD)

 

The most pressing need for NFS server daemons centers around the need for

 

multi-threading NFS RPC requests. Running daemons in user-level processes

 

allows the server to have multiple, independent threads of processes. In this way,

 

the server can handle several NFS requests at once. As a daemon completes the

 

processing of a request, the daemon returns to the end of a line of daemons that

 

wait for new requests. Using this schedule design, a server always has the ability to

 

accept new requests if at least one server daemon is waiting in the queue. Multiple

 

instances of this daemon can perform tasks simultaneously.

 

Mount Daemon (MNTD)

 

Each NFS server system runs a mount daemon which listens to requests from

 

client systems. This daemon acts on mount and unmount requests from clients. If

 

the mount daemon receives a client mount request, then the daemon checks the

 

export table. The mount daemon compares it with the mount request to see if the

 

client is allowed to perform the mount. If the mount is allowed, the mount daemon

 

will send to the requesting client an opaque data structure, the ®le handle. This

 

structure uniquely describes the mounting point that is requested by the client. This

 

will enable the client to represent the root of the mounted ®le system when making

 

future requests.

10OS/400 Network File System Support V4R4

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IBM AS/400E manual RPC Binder Daemon Rpcd, NFS Server Daemons Nfsd, Mount Daemon Mntd
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AS/400E specifications

The IBM AS/400E, now more commonly known as IBM i, is a robust and versatile midrange server that has been designed to provide a comprehensive computing solution for businesses of all sizes. First introduced in the late 1980s, the AS/400 series has undergone multiple enhancements and rebranding, with the AS/400E being one of the notable iterations. This powerful platform is closely associated with IBM's commitment to reliability, scalability, and integrated business solutions.

One of the main features of the AS/400E is its highly integrated architecture that combines hardware and software into a cohesive system. This integration allows for seamless operations, reducing the complexity typically associated with managing disparate systems. The system is powered by IBM's proprietary OS/400 operating system, which has evolved into IBM i, featuring advanced capabilities like object-oriented programming, integrated database management, and security features that are essential for enterprise environments.

A key characteristic of the AS/400E is its robust database support, primarily through the use of DB2 for i. This integrated database management system enables efficient data handling and retrieval, facilitating real-time business analytics and reporting. Furthermore, the platform supports a variety of programming languages, including RPG, COBOL, and Java, making it flexible for developers who require diverse tools for application development.

The AS/400E is also known for its exceptional reliability and uptime, making it a preferred choice for critical business applications in industries such as finance, healthcare, and manufacturing. This reliability is backed by advanced error detection and correction mechanisms, as well as redundancy features that help prevent data loss and minimize downtime.

In terms of scalability, the AS/400E can effortlessly expand to accommodate growing business demands. Organizations can increase processing power by adding more resources without significant disruption. This scalability, combined with the system’s built-in virtualization capabilities, allows businesses to optimize resource usage and streamline operations.

Security is another defining feature of the AS/400E. The platform incorporates various layers of security measures, including user authentication, encryption, and comprehensive auditing capabilities, ensuring that sensitive business data is protected against unauthorized access.

Overall, the IBM AS/400E remains a powerful tool in the enterprise computing landscape, providing businesses with an integrated, reliable, and secure solution for their technological needs. Its enduring popularity is a testament to its capability to evolve with changing business requirements while maintaining its core attributes of high performance and stability.
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