Sponsored Content
Full Discussion: Subnetting
Special Forums IP Networking Subnetting Post 302993556 by drysdalk on Saturday 11th of March 2017 05:36:15 AM
Old 03-11-2017
Hi,

To put it as simply as possible, in any given network range the very first address and the very last address are not usable for hosts. The first address is the network address, and the last address is the broadcast address.

So for 192.168.1.0/24 you'd have:

192.168.1.0 - Network address (NOT usable for hosts)
192.168.1.1 through 192.168.1.254 - Free IPs (Usable for hosts)
192.168.1.255 - Broadcast address (NOT usable for hosts)

And for /25 sub-nets (and all others besides) it'd be the same: the first address in the range and the last address in the range are not usable for hosts.
These 2 Users Gave Thanks to drysdalk For This Post:
 

3 More Discussions You Might Find Interesting

1. IP Networking

Subnetting

We have subnetted our Internal Network. We used an I.P. range of 172.16.16.0-254, 172.16.17.0-254, 172.16.18.0-254, 172.16.19.0-254 and mask 255.255.252.0. We created a subnet range of 172.16.10.0-254 and maske 255.255.255.0. Our routers are configure to route to approprate network. We are able... (2 Replies)
Discussion started by: cassy
2 Replies

2. IP Networking

Subnetting in 11 steps

As seen on Digg.com, here is my ip addressing article in full... Original Subnetting in 11 Steps article Subnetting in 11 Steps There are a few things that you will need to know first. I personally use 11 rules that I learned from Mike Vana. Below you will find the 11 rules as well as... (1 Reply)
Discussion started by: jking2100
1 Replies

3. IP Networking

Subnetting

Guys, Anyone could help me understand subnetting. I know a bit in networking but there are things that I don't get them easily. Thank You in advance. (1 Reply)
Discussion started by: etcpasswd
1 Replies
TCPDROP(8)						    BSD System Manager's Manual 						TCPDROP(8)

NAME
tcpdrop -- drop TCP connections SYNOPSIS
tcpdrop local-address local-port foreign-address foreign-port tcpdrop [-l] -a DESCRIPTION
The tcpdrop command may be used to drop TCP connections from the command line. If -a is specified then tcpdrop will attempt to drop all active connections. The -l flag may be given to list the tcpdrop invocation to drop all active connections one at a time. If -a is not specified then only the connection between the given local address local-address, port local-port, and the foreign address foreign-address, port foreign-port, will be dropped. Addresses and ports may be specified by name or numeric value. Both IPv4 and IPv6 address formats are supported. The addresses and ports may be separated by periods or colons instead of spaces. EXIT STATUS
The tcpdrop utility exits 0 on success, and >0 if an error occurs. EXAMPLES
If a connection to httpd(8) is causing congestion on a network link, one can drop the TCP session in charge: # sockstat -c | grep httpd www httpd 16525 3 tcp4 192.168.5.41:80 192.168.5.1:26747 The following command will drop the connection: # tcpdrop 192.168.5.41 80 192.168.5.1 26747 The following command will drop all connections but those to or from port 22, the port used by sshd(8): # tcpdrop -l -a | grep -vw 22 | sh SEE ALSO
netstat(1), sockstat(1) AUTHORS
Markus Friedl <markus@openbsd.org> Juli Mallett <jmallett@FreeBSD.org> BSD
January 30, 2013 BSD
All times are GMT -4. The time now is 01:10 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy