Free Essay

Nfs (Network File System)

In:

Submitted By dulcio06
Words 387
Pages 2
NFS (Network File system)
IPtables
NFS protocol was developed by SUN microsystems using UNIX. NFS allows severs to share local directories with client systems. NFS runs on UNIX, DOS, Microsoft, VMS, Linux and more. NFS allows a client to access files on a remote server. The client user is usually unaware on the storage location on the file they are using. NFS reduces the storage needs used on the client and aids in the administration work load.
With an NFS the file system stored on a remote server and the directory is shared over a local network. The server has a large capacity disk drive and device so that copies for file can be backed up with a problem. Diskless systems boot from the file server and load the system from a fileserver. Because a diskless client doesn’t require much to run a file server system you can use older machine as clients.
Other options for NFS for Linux are netboot and dataless system. Netboot uses TFTP (Trivial File Transfer Protocol) that runs PXE (Preboot Execution Environment) a boot server for Intel. Dataless systems allow the user to store all files remotely but only Linux based applications can be kept on the disk.
IPtables are composed of two components netfilter and IPtables. Netfilter a set of tables that hold rules the kernel uses to control network packet filtering. IPtables set up, maintain, and displays the rules stored by netfilter. Rules use one more categories matches or classified with single action. The rule that applies to the network packet is matched using the categories and action is applied to packet. Rules are store in chains. Each rule in a chain is applied, in the order, to the packet until a match is found. In the kernel IPtables replaces the earlier Ipchains as a method of filtering network packets. It provides multiple chains for increased filtration flexibility. IPtables requires elevated privileges to operate and must be executed by user root, otherwise it fails to function. On most Linux systems, iptables is installed as /usr/sbin/iptables and documented in its man pages which can be opened using man iptables when installed. It may also be found in /sbin/iptables, but since iptables is more like a service rather than an "essential binary", the preferred location remains /usr/sbin.

Similar Documents

Free Essay

Comparative Operating Systems

...COMPARATIVE OPERATING SYSTEMS TERM PAPER SUMMER 2001 COMPARISON OF NETWORK OPERATING SYSTEMS BY MUKUNDAN SRIDHARAN COMPARISON OF NETWORK OPERATING SYSTEM S Abstract We are in a era of computing in which networking and distributed computing is the norm and not a exception. The ability of a operating system to support networking has become crucial for its survival in the market. In today’s picture there is no operating system, which doesn’t support networking. This paper tries to give a review of various network operating systems or the networking support of a operating system, in relevance to the modern operating systems. The emphasis is on basic design and architecture, not their specifications or services. The paper considers various operating systems like Novell Netware, the sun NFS, the Styx, CIFS/SMB and Microsoft Windows 2000 server. Again the concentration is on modern and evolving operating systems like the Novell Netware and Microsoft’s Windows 2000. The objective of the paper is to study and compare various operating systems and to bring out the inherent advantages and disadvantages in using them. 1.0 INTRODUCTION Individual computers are connected together to form computer networks. The operating system, protocols and services which help us in interconnecting the computers are collectively called Network Operating systems. The webopedia.com defines Network Operating Systems as follows: An operating system that includes special...

Words: 12519 - Pages: 51

Free Essay

History on Nfs

...The first network file system—called File Access Listener—was developed in 1976 by Digital Equipment Corporation (DEC). An implementation of the Data Access Protocol (DAP), it was part of the DECnet suite of protocols. Like TCP/IP, DEC published protocol specifications for its networking protocols, which included the DAP. NFS was the first modern network file system (built over the IP protocol). It began as an experimental file system developed in-house at Sun Microsystems in the early 1980s. Given the popularity of the approach, the NFS protocol was documented as a Request for Comments (RFC) specification and evolved into what is known as NFSv2. As a standard, NFS grew quickly because of its ability to interoperate with other clients and servers. The standard continued to evolve into NFSv3, defined by RFC 1813. This iteration of the protocol was much more scalable than previous versions, supporting large files (larger than 2GB), asynchronous writes, and TCP as the transport protocol, paving the way for file systems over wide area networks. In 2000, RFC 3010 (revised by RFC 3530) brought NFS into the enterprise setting. Sun introduced NFSv4 with strong security along with a stateful protocol (prior versions of NFS were stateless). Today, NFS exists as version 4.1 (as defined by RFC 5661), which adds protocol support for parallel access across distributed servers (called the pNFS extension). The timeline of NFS, including the specific RFCs that document its behavior, is shown...

Words: 1317 - Pages: 6

Free Essay

Linux Unit 5

...First, let us analyze what file sharing in a centralized storage area on a server means. It means that basically when you store a file it will be stored in a predetermined place on a server instead of on the system. Now let us analyze what file replication is. File replication would be the server backing up by replicating to another server. Both of these are extremely helpful services provided by servers. How are these beneficial services increasing the ease of administration? Well, all of the different users will be storing their work to the server. That means they can login and access their files from any workstation on the local network. So I have come up with some examples showing different scenarios where this would be helpful. Example 1: As a student, if all of your files were being stored on a server you could login from any computer and access your files allowing for great mobility. Example 2: This one isn’t about a local network but I felt it was a great example anyway. When your access your e-mails they are stored on a server. Allowing you to login from anywhere and access the mail. Also, you can send yourself attachments so that you can access them at any time from any place. Example 3: Say you work in a lab and you want to do an experiment. You could search the server to find helpful information from other people’s work that is being shared. All of these examples benefit from replication as well. These servers replicating which would be backing up to the other servers...

Words: 492 - Pages: 2

Free Essay

Nt1430W5Essay

...NT1430 NFS NFS is an open standard, cross-platform file system utility with implementations available for a wide range of operating systems, architectures, platforms, and appliances, from embedded systems to mainframes and high-performance clusters. NFS provides file sharing for Unix, Linux, mainframes, and other file systems, including Mac OS X. A Network File System (NFS) allows remote hosts to mount file systems over a network and interact with those file systems as though they are mounted locally. This enables system administrators to consolidate resources onto centralized servers on the network. Currently, there are three versions of NFS. NFS version 2 (NFSv2) is older and is widely supported. NFS version 3 (NFSv3) has more features, including 64bit file handles, Safe Async writes and more robust error handling. NFS version 4 (NFSv4) works through firewalls and on the Internet, no longer requires portmapper, supports ACLs, and utilizes stateful operations. Red Hat Enterprise Linux supports NFSv2, NFSv3, and NFSv4 clients, and when mounting a file system via NFS, Red Hat Enterprise Linux uses NFSv3 by default, if the server supports it. All versions of NFS can use Transmission Control Protocol (TCP) running over an IP network, with NFSv4 requiring it. NFSv2 and NFSv3 can use the User Datagram Protocol (UDP) running over an IP network to provide a stateless network connection between the client and server. When using NFSv2 or NFSv3 with UDP, the stateless UDP connection...

Words: 350 - Pages: 2

Free Essay

Sharing Files with Nfs

...7 Sharing Files with NFS Network File System (NFS) is a distributed file system protocol originally developed by Sun Microsystems in 1984, allowing a user on a client computer to access files over a network much like local storage is accessed. NFS, like many other protocols, builds on the Open Network Computing Remote Procedure Call (ONC RPC) system. The Network File System is an open standard defined in RFCs, allowing anyone to implement the protocol. NFS is the most-known service using remote procedure call (RPC). It is an excellent way of sharing files between Linux and other UNIX systems. NFS also allows for machines to mount without authentication, at boot, which is great if you have a cluster of systems or if you want to use a centralized home directory system (using an NFS-mounted directory for home directories to keep your configurations and files identical on multiple systems). The computer where directory located is called the server and computers or devices connecting to that server are called clients. Clients usually 'mount' the shared directory to make it a part of their own directory structure. NFS is perhaps best for more 'permanent' network mounted directories such as /home directories or regularly accessed shared resources. If you want a network share that guest users can easily connect to, Samba is more suited. This is because tools exist more readily across old and proprietary operating systems to temporarily mount and detach from Samba shares. NFS is also very...

Words: 711 - Pages: 3

Free Essay

Nfs Security

...Linux NFS Paper Today I will be talking about NFS, or Network File system, and it used widely to share files across multiple servers and computers. Let me just clarify how the NFS system will work, a file will be taken from the directory, or NFS file system, the file will then be exported to the NFS client, then you would need to mount the file to the client, to make sure it was accessible throughout the entire system. With the system mount you can also see the IP addresses accessing the system, which isn’t that secure, seeing how anyone could simply scam their way into your system, which you really want to protect against. Today we want to learn how to properly secure that you have to cover the 3 main resources, or places to secure. The Portmapper, the server security, and the client security are the 3 things you must secure. The Portmapper is basically the root to the NFS, you want to make sure the ports are being used correctly, and are giving access to the right people, and is connected to an outside trusted network. You can simply use the etc/hosts command to check the ports, but you can also use that to allow and deny ports to anybody across the network. That’s a bit drastic, but can lead to a secure NFS especially if you notice any fishy IP addresses or activities across the network. With the server security, this is where it becomes more of a necessity to keep it secure, because without system security, the whole thing is going to go down the drain. It would be...

Words: 461 - Pages: 2

Free Essay

Linux Essay

...File sharing through the network is just as easy as saving a file to a floppy disk, flash drive, or CD-ROM. You can send the file over a network connection, instead of saving the file to a storage device and personally hand delivering it, or sending it. Some file transferring such as email, have limited space for file sharing. You can use multiple different ways of transferring files. File transfers such as (P2P) known as peer to peer act as a client, and server. (P2P) allows larger transfers of file sharing, but does not use a central server. File sharing helps administration because, you can still have the security of the file that may be needed for business, or personal needs. Storing files in a central server allows only clients with permissions of the file. Files can be encrypted to protect information, and you have to have a password to access the content of the file. File sharing is better than using an external device since, external devices can be lost, or stolen. Sharing a file through a network allows the encryption to protect the permissions of the file, and only clients eligible of the content can see it. A good example of having file sharing instead of an external device is, when you have a extended business that needs to reach out to other owned locations. Instead of spending more money for external devices to be sent through the mail, which takes time and the package may not ever make it to the destination. Why not send the information through the network...

Words: 486 - Pages: 2

Free Essay

Project Part 2 Task 1

...Secure File Storage Server Scenario There is a requirement to read customer confidential data located in the local area network (LAN) of First World Bank Savings and Loan. The organization needs to deliver highly confidential customer data in Portable Document Format (PDF) format for its online customers. This data is typically uploaded to a Linux file server by the bank employees within the LAN. However, online customers need to have access to their particular data. At the same time, the customers should not be able to modify the data. Tasks You need to: Design a file storage server architecture for the proposed Web-based infrastructure to support customers. Describe specifically how data can be shared with the Web server in a secure fashion. Submission Requirements Format: Microsoft Word Font: Arial, Size 12, Double-Space Citation Style: Chicago Manual of Style Length: 1–2 pages Due By: Unit 5 Self-Assessment Checklist I have explained how a Linux server can read data from a secure server in the local network. I was able to understand Linux filesystem mounting options. I have recommended an appropriate network sharing service. In the scenario that there is a requirement to read customer data that is confidential located in the local area network (LAN) of First World Bank Savings and Loan, & at the same time, online customers need to have access to their data but not be able to modify the data. This is accomplished by the design of the file server...

Words: 574 - Pages: 3

Premium Essay

Creatimg a Network Solution

...Create a Network Solution Name: Course: Tutor: Date: Create a Network Solution. Many methods of using computer networks for data storage have come up in recent years. The most common and popular approach which I personally prefer is the network attached storage (NAS).NAS allows businesses more affordably that before to store and retrieve large amounts of data. Most businesses do not consider the future expansion of their companies when creating their network solutions and end up exhausting their network resources. The increase in the data capacities of the electronic components used in today business world has led to the demand for a more convenient storage type. The ability to use a file server to store files has led to companies deploying large centralized NFS servers which are accessed by thousands of clients. Central file servers are seen as the basic solution to demands put forward. A file server is in basic terms a workstation or a personal computer hardware running on a network operating system (NOS).The NOS in this case boasts file sharing capabilities. The hard drives installed in the computers are used to provide the required storage space ranging from gigabytes to terabytes of memory space depending on the size of business. Many business owners are not justified by the use of a fully general-purpose computer as a server for simple storage services. This factor brought to the development of the network attached storage (NAS). NAS creates a system that...

Words: 1467 - Pages: 6

Premium Essay

Homework 7

...Chapter Exercises 1. Certain Ethernet adapters for ISA PC systems have limitations which can lead to serious network problems, particularly with NFS. This difficulty is not specific to FreeBSD, but FreeBSD systems are affected by it. 2. You must check if the directory you want to mount is actually exported on the NAS Gateway 500. To check what file systems, directories, or files are exported from NAS Gateway 500, use the showmount command. If NAS Gateway 500 doesn’t respond to the showmount command, you should check if the NFS server daemons are running at NAS Gateway 500. 3. By manually editing the NFS configuration file, and through the command line, i.e. through exportfs. 4. Read-write/ 192.16.0.0/var/ITT-Tech library 5. Refer to lab. 6. NFS attribute caching can cause inconsistencies when large numbers of client nodes are asked to access files that have been updated recently and the attribute caching data on the client has not expired. Disabling attribute caching eliminates the problem but may degrade performance for frequent file operations requiring file attribute data. 7. Mountfs 8. Diskless system - is a workstation or personal computer without disk drives, which employs network booting to load its operating system from a server. PXE boot - is an environment to boot computers using a network interface independently of data storage devices (like hard disks) or installed operating systems. Dataless system - Diskless and dataless clients are machines that are not...

Words: 260 - Pages: 2

Free Essay

Project Part 2 - Executive Summary

...a requirement for a customer to read confidential data but not modify it, and at the same time any information to be modified by authorized personnel. This data to be stored on the LAN of the First World Bank Savings and Loan. First it is listed the there should be some sort of Anti-virus/Anti-malware that runs with the solutions and services on the Linux network. This provides multi-layered security for the servers, and at the same time, protects the file system in real-time. This allows users to view the data without manipulating it. The Second is the recommended network sharing service. Network File Service (NFS) is recommened where access is through Secure Socket Layer (SSL). NFS allows the mounting of file systems on remote computers, & access to them. The client or accessing computer would just need to be running NFS client which is compatible with the NFS server. This is done with the mount points, and after the share or file, is mounted, all I/O operations are written back to the server. All clients then notice the change instantaneously, as if it was on the local filesystem. Lastly it is recommended to use NFS with access to the LAN via SSL. The encryption that is used will make sure that the data is not compromised and is kept within the C-I-A...

Words: 251 - Pages: 2

Free Essay

Network Attached Storage System

...per byte. In recent years, the amount of storage sold almost doubled each year and is expected to sustain annual growth of at least 60%. Secondary storage has a healthy place in future computer systems. While many storage products are directly attached to personal computers, most disk array products (65% and rising) are deployed in local area network file servers. This centralization of storage resources enables effective sharing, better administrative control and less redundancy. However, it also increases dependence on network and file server performance. With the emergence of high-performance cluster systems based on commodity personal computers and scalable network switching, rapidly increasing demands on storage performance are anticipated. Specifically, storage performance must cost-effectively scale with customer investments in client processors, network links and storage capacity. Unfortunately, current distributed file system architectures severely limit scalable storage. In current distributed file systems, all storage bytes are copied through file server machines between peripheral buses (typically SCSI) and client LANs. In essence, these file server machines act as application-level inter-network routers, converting namespaces (disk block versus file range) and protocol layers (SCSI versus RPC/UDP/IP). This is a critical limitation for cost-effective scalable storage. Specifically, the sustained bandwidth of storage devices is rapidly outstripping ...

Words: 1229 - Pages: 5

Free Essay

Storage Networking

...CNIT 34200 Description Lab 1 – Storage Networking This laboratory activity introduces key storage networking concepts. Using an open source SAN/NAS solution you will build a network storage server that provides both block and file level storage across the network. Using virtualization technologies multiple operating systems will be configured to use the network storage. We will use a rolling check-off approach in this laboratory. You may check off progress at any point of a phase’s duration. The final check-off date is the last day on which you may check off objectives for full credit. For Phases I and II partial credit will be available for up to one week after the final phase check off. Please be sure to review the notes section at the end of this document before beginning the lab. There is adequate time to complete these objectives if you plan and manage your people resources well. However, if you get behind it will quickly snowball. It is highly suggested that you have everything in Phase I other than VM installation completed by Martin Luther King Day. Objectives Phase I – Three weeks  Implement a NetGear GS108T gigabit switch for management and iSCSI traffic. A sample configuration is shown in figure 1. Port Tagged 802.1q VLAN 1 2 3 4 1 & 101 5 1 & 101 6 7 8 Untagged 802.1q VLAN 1 101 1 PVID (if required) 1 101 1 1 1 1 1 1 Attached Host 1 1 1 Uplink to NET SAN iSCSI Interface SAN Mgmt Interface ESXi 1 ESXi 2 Client 1 Client 2 Client 3 Figure 1 – VLAN...

Words: 1568 - Pages: 7

Premium Essay

Unit 4 Summray

...Virtualization * P2P File Sharing * Network Hardware * Windows Networking * Mac OS + iOS Networking * Network Design / IT * Bluetooth Wireless * VoIP - Voice Over IP * Free Practice Tests * Fundamentals Most Popular * What Is Computer Networking? * Introduction to Area Networks * What Is a Network Router? * What Is an Ethernet Card? * Useful Facts About How Wi-Fi Works * Internet Connection Alternatives for Home Networks * More » * Get Connected Most Popular * What Is Computer Networking? * Introduction to Area Networks * What Is a Network Router? * What Is an Ethernet Card? * Useful Facts About How Wi-Fi Works * Internet Connection Alternatives for Home Networks * More » * Uses and Upgrades Most Popular * What Is Computer Networking? * Introduction to Area Networks * What Is a Network Router? * What Is an Ethernet Card? * Useful Facts About How Wi-Fi Works * Internet Connection Alternatives for Home Networks * More » * All Computing Topics * Assistive Technology * Computer Peripherals * Mobile Office Technology * PC Hardware / Reviews * PC Support * Printers / Scanners * More » * Share * Print Ads: * San NAS Storage * Networking Storage * Wireless Network Devices * NAS伺服器 * NAS ...

Words: 983 - Pages: 4

Premium Essay

This Is Not a Test

...created your kernel source code backup.) * chmod - options to recursively change user, group and other permissions on files/directories * chown - options to recursively change file and directory user ownership * chgrp - options to recursively change file and directory group ownership * kill - superkill vs sending other signals to a process * ps - options to list all running processes on a Linux/Gnu system * top – Interactive Linux Tasks Status Display * grep - know how to use to find specific lines of info in output/files (you should have learned about this command in Intro to Unix/Linux Systems.) Shell expansion characters - be able to respond to questions regarding usage of '*' - asterisk, all files or all matching strings '?' - question mark, single character  What are the components of a Linux distribution? * Kernel * Desktop Environment * System Libraries * System Tools * Developmental Tools * File Structure Popular Distributions:  * Redhat,  * CentOS * Fedora  * Suse * Debian * Ubuntus What sort of hardware architecture can Linux be installed on? * Intel-x86 systems * Embedded systems From what sources can Linux be installed? * CD- ROM * Hard Disk * Floopy Disk * USB * Network Installation * ftp * http * nfs Who created the Linux Kernel? What does open source mean? Where is the kernel stored on a CentOS distro (/boot), What...

Words: 4587 - Pages: 19