LinuxQuestions.org
Visit Jeremy's Blog.
Home Forums Tutorials Articles Register
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Newbie
User Name
Password
Linux - Newbie This Linux forum is for members that are new to Linux.
Just starting out and have a question? If it is not in the man pages or the how-to's this is the place!

Notices


Reply
  Search this Thread
Old 10-04-2020, 11:43 PM   #1
bellsal
Member
 
Registered: Aug 2007
Posts: 42

Rep: Reputation: 0
Question IP/Number


Hi All,

I was setting up NFS on my Server/Client machines, and through my searches on LinuxQuestions.org, I found thread that helped me, and my NFS Server/Client are working great. However, in that thread it said: "Try exporting as 192.168.0.0/24".

what does the "/24" after that IP number means? What effect does it have?

Thanks
 
Old 10-05-2020, 01:14 AM   #2
berndbausch
LQ Addict
 
Registered: Nov 2013
Location: Tokyo
Distribution: Mostly Ubuntu and Centos
Posts: 6,316

Rep: Reputation: 2002Reputation: 2002Reputation: 2002Reputation: 2002Reputation: 2002Reputation: 2002Reputation: 2002Reputation: 2002Reputation: 2002Reputation: 2002Reputation: 2002
Quote:
Originally Posted by bellsal View Post
what does the "/24" after that IP number means? What effect does it have?
This is the so-called prefix. It tells you how many bits in the IP address are used for the network number. Since an IPv4 address is 32 bits long, the remaining 8 bits are use as the device address.

You could also say that your netmask is 255.255.255.0. Again, the three 255 bytes are 24 bits set to 1.

The effect is that your network can contain addresses from 196.168.0.1 to 196.168.0.254 (Device addresses 0 and 255 are reserved).

See also https://en.wikipedia.org/wiki/Subnetwork.

This is fundamental networking knowledge. I suggest you study a book or a web page that introduces computer networking, e.g. https://www.dummies.com/computers/computer-networking/ (not implying you are a dummy ).
 
Old 10-05-2020, 12:12 PM   #3
JZL240I-U
Senior Member
 
Registered: Apr 2003
Location: Germany
Distribution: openSuSE Tumbleweed-KDE, Mint 21, MX-21, Manjaro
Posts: 4,629

Rep: Reputation: Disabled
Quote:
Originally Posted by berndbausch View Post
This is the so-called prefix. It tells you how many bits in the IP address are used for the network number. Since an IPv4 address is 32 bits long, the remaining 8 bits are use as the device address...
...hence the /24 means the first 24 bits of the IPv4 address are not resolved / evaluated, right?
 
Old 10-05-2020, 12:33 PM   #4
MadeInGermany
Senior Member
 
Registered: Dec 2011
Location: Simplicity
Posts: 2,791

Rep: Reputation: 1201Reputation: 1201Reputation: 1201Reputation: 1201Reputation: 1201Reputation: 1201Reputation: 1201Reputation: 1201Reputation: 1201
Rather the opposite is true here:
The first 24 bits of the IPv4 address decide if access is granted.
 
Old 10-05-2020, 12:49 PM   #5
JZL240I-U
Senior Member
 
Registered: Apr 2003
Location: Germany
Distribution: openSuSE Tumbleweed-KDE, Mint 21, MX-21, Manjaro
Posts: 4,629

Rep: Reputation: Disabled
That's right, I should have written "... the /24 means the first 24 bits of the IPv4 address are not used for device addresses". Thanks for the clarification .
 
  


Reply

Tags
nfs exports



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off



Similar Threads
Thread Thread Starter Forum Replies Last Post
Identify and explain the major number, minor number, and revision number in Linux... turbomen Linux - Newbie 1 11-16-2010 02:48 AM
Preserving number of links with 'cp'. ( preserve number of links ) Devyn Linux - General 7 09-16-2005 10:07 PM
what is a major number and a minor number ? Menestrel Linux - Newbie 2 10-11-2004 07:53 AM
how do you edit your virtual console number? (or VT number 3) jjorloff1 Linux - General 2 04-03-2004 07:21 PM
why there is a need for minor number and major number for monitor/keyboard in pc? tripathi Solaris / OpenSolaris 1 11-07-2003 09:36 AM

LinuxQuestions.org > Forums > Linux Forums > Linux - Newbie

All times are GMT -5. The time now is 06:27 AM.

Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration