←February→
Sun |
Mon |
Tue |
Wed |
Thu |
Fri |
Sat |
|
|
|
|
|
|
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 |
14 |
15 |
16 |
17 |
18 |
19 |
20 |
21 |
22 |
23 |
24 |
25 |
26 |
27 |
28 |
|
| ←2025→Months |
Jan |
Feb | Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
|
Wed, Sep 25, 2024 10:17 pm
Viewing network connections on a Microsoft Windows system by protocol
If you just wish to see
TCP ports in use on a Microsoft Windows system,
you can issue the
netstat -a -p TCP
command at a command prompt.
The
-a
parameter specifies all connections and listening
ports should be displayed while the
-p
parameter can be
used to select a
protocol from TCP,
UDP, TCPv6, or UDPv6. If used with the
-s
option to display per-protocol statistics, the protocol
argument may be any of:
IP,
IPv6,
ICMP, ICMPv6, TCP, TCPv6, UDP, or
UDPv6. If you only wish to view IPv6 TCP ports in use,
you can use
netstat -a -p TCPv6
. If you only wish to
see currently established connections, you can
pipe the output of
the
netstat
command to the
find
command. E.g.,
netstat -a -p TCP | find "ESTABLISHED"
. Or, if you wished to
see all of the TCP ports on which the system was listening for a connection,
you could use
netstat -a -p TCP | find "LISTENING"
. If you
wanted to see connections to a particular port, e.g., 22, for Secure
Shell (SSH) connections, you could use
netstat -a | find ":ssh"
, which would show the IP addresses of the remote systems connected
via SSH, or
netstat -a | find ":https"
for
HTTPS connections to web sites. If you wished to see host names rather than IP addresses, you could
add the
-f
option, which displays a
Fully Qualified Domain Name
(FQDN) instead of an IP address for a remote system. E.g.,
netstat -a -f | find ":https"
. Since SSH, HTTP, and HTTPS
use TCP rather than UDP transmissions, you don't need to add the
-p
parameter.
[/os/windows/network]
permanent link
Sun, Mar 31, 2024 8:11 pm
Configuring PuTTY for X forwarding
The
X Window System,
aka X11 or simply X, provides a mechanism that allows you to have the
graphical
user interface (GUI) for an application running on a remote system to
be displayed on the system on which you are running X server software. For
systems running a Microsoft Windows operating system, you can use the
free
PuTTY program to
establish a
Secure Shell (SSH)
connection to an
SSH server
and configure PuTTY to allow X forwarding so that you can run programs on the
SSH server, but have their GUI displayed on the Microsoft Windows system on
which you are running PuTTY.
[ More Info ]
[/os/windows/network/ssh/putty]
permanent link
Sat, Mar 02, 2024 9:01 pm
Location for PuTTY Tunnel Information
PuTTY stores information
about sessions you have created to connect to a particular host in the
Windows Registry at
HKEY_CURRENT_USER\SOFTWARE\SimonTatham\PuTTY\Sessions
.
If you want to view the SSH tunnels configured for a particular host, i.e.,
the
port forwarding
settings for that host, you can navigate to
HKEY_CURRENT_USER\SOFTWARE\SimonTatham\PuTTY\Sessions\SessionName\PortForwardings
where
SessionName is the name you have given to the session
associated with the host. E.g., suppose you regularly establish an
SSH
connection to www.example.com and have named a session for that site
MySite
. You could navigate to
HKEY_CURRENT_USER\SOFTWARE\SimonTatham\PuTTY\Sessions\MySite\PortForwardings
to find the port forwardings settings. If you had named the session
My Site
, there would be a
%20
in the session name
stored in the registry as
%20
is an HTML representation for the
space character. You can doubleclick on the
PortForwardings
key
in the right pane of the registry window to see the values stored in the key.
You might see something like the following:
L22011=192.168.0.11:22,L33018=192.168.0.18:33018
[
More Info ]
[/os/windows/network/ssh/putty]
permanent link
Sun, Jan 21, 2018 10:56 pm
OpenVPN
OpenVPN is
free and open-source software that provides
Virtual Private Network (VPN) connectivity that is available for a variety
of
operating systems. To use the software on a
Microsoft Windows 10 system, download the the installer for
Windows
Vista and later from the OpenVPN
Community Downloads page; get the OpenVPN community software not the
PrivateTunnel software from the OpenVPN project - I mistakenly downloaded
and installed PrivateTunnel when I first went to the
OpenVPN site and then had to
uninstall PrivateTunnel.
[ More Info ]
[/os/windows/network/vpn]
permanent link
Mon, Jan 15, 2018 7:37 pm
Using the Windows Resource Monitor to monitor network activity
If you want to see the IP addresses to which a program on a Microsoft Windows
system is establishing connections, you can use the
Resource Monitor utility that is provided with
Windows
Vista and later versions of Windows to check on network connections from
a particular application on the system. To start the program, you can click
on the Windows
Start button and type resmon
or resmon.exe
in the "Search programs and files" field on a Windows 7 system or the
"Type here to search" field on a Windows 10 system. You should see the
resmon utility returned as the best match.
When the Resource Monitor program is running, you can click on the
Network tab and then TCP Connections to see network activity
associated with programs currently running on the system . You can click on a
column header, e.g. "Image" to sort the entries by the values in that column.
[ More Info ]
[/os/windows/network/monitoring/resmon]
permanent link
Sat, Jan 21, 2017 11:33 pm
Error occurred message when upgrading freeSSHd
I needed to upgrade
freeSSHd, which
is free
Secure Shell (SSH) server software for Microsoft Windows systems, on a
Windows 8 system. The software allows remote users to log into a command line
interface on the Windows system via SSH and provides the capability to transfer
files via the
SSH File Transfer Protocol (SFTP). When I attempted to
install the latest version of the software over a prior version, however, the
installation was unsuccessful. If you see the following error message, you may
need to stop the SSHD service prior to performing the upgrade:
An error occurred while trying to replace the existing file:
DeleteFile failed; code 5.
Access is denied.
Click Retry to try again, Ignore to skip this file (not recommended), or
Abort to cancel installation.
[ More Info ]
[/os/windows/network/ssh/freeSSHd]
permanent link
Sat, Mar 19, 2016 10:51 pm
Determining which program is listening on a port under Windows
If you want to know which application is listening on a particular
network port on a Microsoft Windows system, e.g., port 80, the port used
for HTTP connections to a web server, you can obtain that information
from a command line interface (CLI) by
obtaining a command prompt and
using the netstat and tasklist commands which are provided with the
operating system; you do not need to install any additional software,
though there are programs that will allow you to view that information
from a graphical user interface (GUI).
[ More Info ]
[/os/windows/network]
permanent link
Mon, Feb 29, 2016 11:07 pm
Using SSH Keys with PuTTY
PuTTY is a
free and open source network utility that allows you to establish
Telnet and
Secure
Shell (SSH) connections to servers. It is commonly used on Microsoft
Windows systms, but is also available for
Linux and
Apple
OS X
systems. You can use it for interactive SSH logins where you provide a
userid and password to authenticate with an SSH server, but you can also use
it for
public key-based logins where the server has a public key
that is matched against a private key stored on the system from which you
are connecting. By a mathematical calculation based on large
prime
numbers, the public key and private key can be matched with one another
as a means of authenticating the login.
[ More Info ]
[/os/windows/network/ssh/putty]
permanent link
Sun, Feb 14, 2016 1:40 pm
Determining if a Windows system supports the 5 GHz Wifi band
The
Wi-Fi
network adapter in a Microsoft Windows system may support
dual
band wireless connections, i.e, both the 2.4 GHz and 5 GHz bands for a
wireless local area network (WLAN), or it may only only support the older
2.4 GHz standard. A
radio
frequency (RF) band is is a group of frequencies containing many channels.
To determine if a wireless adapter can support both the 2.4 and 5 GhZ Wifi
standards, you can
obtain a command
prompt and type the command
netsh wlan show drivers
. If
you see 802.11a listed on the "Radio types supported line, then the adapter
supports the 5 GHz as well as the 2.4 GHz bands.
[ More Info ]
[/os/windows/network]
permanent link
Sun, Feb 07, 2016 8:04 pm
Changing the appearance of a PuTTY session
If you wish to be able to easily distinguish
Secure Shell (SSH) sessions to a particular
server when using
PuTTY,
a
free and open-source SSH and
Telnet
client application available for Microsoft Windows, OS X, and Linux
systems, you can change the background color used for connections
to a particular server through PuTTY's "Change Settings" option,
which will allow you to change the background and foreground colors
(the foreground color is used for text). Colors are specified by
RGB value.
[ More Info ]
[/os/windows/network/ssh/putty]
permanent link
Privacy Policy
Contact