LinuxQuestions.org
View the Most Wanted LQ Wiki articles.
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Networking
User Name
Password
Linux - Networking This forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.

Notices



Reply
 
Search this Thread
Old 09-10-2005, 12:52 AM   #1
abefroman
Senior Member
 
Registered: Feb 2004
Location: lost+found
Distribution: CentOS
Posts: 1,278

Rep: Reputation: 53
If I have 10.10.0.130/30 what are my usable ips?


If I have 10.10.0.130/30 what are my usable ips?
 
Old 09-10-2005, 03:26 AM   #2
logicalfuzz
Member
 
Registered: Aug 2005
Distribution: Arch Linux
Posts: 291

Rep: Reputation: 41
10.10.0.130/30 means 30 network bits out of a total of 32 bits. that leaves only 2 bits for host. so you can have not more than 4 hosts. ie. the mask would be
11111111 11111111 11111111 111111xx
which sums up to 255.255.255.252.

ANDing 10.10.0.130 with the mask would give a range
10.10.0.128 to 10.10.0.131

has to be correct, but i have just started learning the ropes in the n/w ing world. point out flaws if any.

Last edited by logicalfuzz; 09-10-2005 at 01:20 PM.
 
Old 09-10-2005, 09:07 AM   #3
archtoad6
Senior Member
 
Registered: Oct 2004
Location: Houston, TX (usa)
Distribution: MEPIS, Debian, Knoppix,
Posts: 4,727
Blog Entries: 15

Rep: Reputation: 231Reputation: 231Reputation: 231
Check out ipcalc, esp. the one that comes w/ Debian:
Code:
# ipcalc -v
0.40

# ipcalc 10.10.0.130/30
Address:   10.10.0.130          00001010.00001010.00000000.100000 10
Netmask:   255.255.255.252 = 30 11111111.11111111.11111111.111111 00
Wildcard:  0.0.0.3              00000000.00000000.00000000.000000 11
=>
Network:   10.10.0.128/30       00001010.00001010.00000000.100000 00
HostMin:   10.10.0.129          00001010.00001010.00000000.100000 01
HostMax:   10.10.0.130          00001010.00001010.00000000.100000 10
Broadcast: 10.10.0.131          00001010.00001010.00000000.100000 11
Hosts/Net: 2                     Class A, Private Internet
You can't see it here, but the coloring in the output is very helpful.


Even the version (# unknown, -v doesn't work) that comes w/ RH/FC has merit:
Code:
$ ipcalc -bmnp 10.10.0.130/30
NETMASK=255.255.255.252
PREFIX=30
BROADCAST=10.10.0.131
NETWORK=10.10.0.128
 
  


Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

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
Iptables newbie: Avoiding connections from 130.40.23.12 guarriman Linux - Networking 1 10-10-2005 03:17 PM
Microsoft MN-130 NIC in Fedora globalgreg Fedora 2 03-06-2005 11:39 AM
Installing ethernet MN-130 fiorejm Linux - Hardware 2 10-10-2004 04:34 PM
how to define a specific range of IPs and/or multiple IPs in an iptables rule?... TheHellsMaster Linux - Security 9 09-20-2004 11:06 AM
Using a Microsoft MN-130 PCI Adapter on Linux tenn_eric Linux - Hardware 3 10-29-2003 02:38 AM


All times are GMT -5. The time now is 07:21 PM.

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
identi.ca: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration