sorted by: recent | see :
popular
Content Tagged with address + Debian
Cisco Layer 2 Switch Functions
Layer 2 switch is A network device that forwards traffic based on MAC layer (Ethernet or Token Ring) addresses.
Bridging technology has been around since the 1980s (and maybe even earlier). Bridging involves segmentation of local-area networks (LANs) at the Layer 2 level. A multiport bridge typically learns about the Media Access Control (MAC) addresses on each of its ports and transparently passes MAC frames destined to those ports. These bridges also ensure that frames destined for MAC addresses that lie on the same port as the originating station are not forwarded to the other ports. For the sake of this discussion, we consider only Ethernet LANs.
Layer 2 switches effectively provide the same functionality. They are similar to multiport bridges in that they learn and forward frames on each port. The major difference is the involvement of hardware that ensures that multiple switching paths inside the switch can be active at the same time.
There are three distinct functions of layer 2 switching
1)address learning
2)forward/filter decisions
3)loop avoidance
Address learning
Layer 2 switches and bridges remember the source hardware address of each
frame received on an interface, and they enter this information into a MAC database called a forward/filter table.
Forward/filter decisions
When a frame is received on an interface, the switch looks at the destination
hardware address and finds the exit interface in the MAC database. The frame is only
forwarded out the specified destination port.
Loop avoidance
If multiple connections between switches are created for redundancy purposes,
network loops can occur. Spanning Tree Protocol (STP) is used to stop network loops
while still permitting redundancy.
Tags: Cisco Layer 2 Switch Functions, cisco switch Loop avoidance, layer2 switch address learning, NetworkCisco Layer 2 Switch Functions, cisco switch Loop avoidance, layer2 switch address learning, Network addthis_url = 'http%3A%2F%2Fwww.debianadmin.com%2Fcisco-layer-2-switch-functions.html'; addthis_title = 'Cisco+Layer+2+Switch+Functions'; addthis_pub = 'david23';
©2008 Debian Admin. All Rights Reserved.
.Debian: Debian Admin Step By Step Tutorials and articles with screenshots
Howto bind ssh to selected IP address
ssh (SSH client) is a program for logging into a remote machine and for executing commands on a remote machine. It is intended to replace rlogin and rsh, and provide secure encrypted communications between two untrusted hosts over an insecure network. X11 connections and arbitrary TCP ports can also be forwarded over the secure channel.
We all know, by default installation of openssh daemon service (sshd), it binds itself to all existing IP address from given host.
Alternatively, if you wish to bind sshd service to selected IP address, this is possible by simply editing /etc/ssh/sshd_config file.
First, always make a backup copy of conf files you wish to edit.
# cp /etc/ssh/sshd_config /etc/ssh/sshd_config.backup
Launch your fave text editor and edit /etc/ssh/sshd_config
#vi /etc/ssh/sshd_config
Go to specific lines that shows
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ListenAddress *
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
If you wish to bind ssh to existing 2 IP address, let’s say 192.168.1.5 and 192.168.1.7 , this could be done by changing the above sshd_config lines to
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ListenAddress 192.168.1.5
ListenAddress 192.168.1.7
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
and Restart sshd daemon using the following command
# service sshd restart
One applicable instance that his can be useful is that when you have a group of ssh users and there are times you need to disconnect all those currently logged in ssh users except your own remote ssh connections. This can be simply done by shutting down the other interface from where those ssh users are currently connected. And ofcourse, you need to be currently connected with the other interface before shutting down the other interface or IP address.
Tags: bind ssh to selected IP address, bind ssh to selected IP address in linux, bind ssh to static ip addressbind ssh to selected IP address, bind ssh to selected IP address in linux, bind ssh to static ip address addthis_url = 'http%3A%2F%2Fwww.debianadmin.com%2Fhowto-bind-ssh-to-selected-ip-address.html'; addthis_title = 'Howto+bind+ssh+to+selected+IP+address+'; addthis_pub = 'david23';
©2007 Debian Admin. All Rights Reserved.
.Debian: Debian Admin Step By Step Tutorials and articles with screenshots
Private and Public IP Addresses Explained
Public IP Addresses
What is Public IP address
Public IP Addresses (also known as Static IP Addresses) are IP addresses that are visible to the public.Because these ip addresses are public, they allow other people to know about and access your computer, like a Web server.In some cases, you do not want people to access your computer or you want to restrict certain individuals from accessing your computer or server.
What is Private IP address
These addresses can be used on a private network, but they’re not routable through the public Internet. This not only creates a measure of much-needed security, but it also conveniently saves valuable IP address space.
Current Private IP addresses as follows
Class A
10.0.0.0 through 10.255.255.255
Class B
172.16.0.0 through 172.31.255.255
Class C
192.168.0.0 through 192.168.255.255
Tags: Network, private ip address, private ip address range, public ip address, what is private ip address, what is public ip addressNetwork, private ip address, private ip address range, public ip address, what is private ip address, what is public ip addressDebian: Debian Admin Step By Step Tutorials and articles with screenshots
Debian Networking for Basic and Advanced Users
Debian: Debian Admin Step By Step Tutorials and articles with screenshots
Change your Network card MAC ( Media Access Control) address
Debian: Debian Admin Step By Step Tutorials and articles with screenshots
install
changer
change
address
Examples
Mac
network
Ubuntu
Debian
your
