Ip Scan For Open Ports
TCP Port Scanner. With this online TCP port scanner you can scan an IP address for open ports. Use this TCP port scan tool to check what services (apache, mail, ssh, ftp, mysql, telnet, dns) are running on your server, test if your firewall is working correctly, view open TCP ports. That's how a port scanner works. My server is not trying to hack you. Please don't contact us or our datacenter, complaining that you are getting hacked. Instead, read a book on how the TCP/IP protocol works, and understand your own actions. Port Number List. This is a fairly complete and up to date listing of port numbers: IANA Port Number List.
Simply put, Angry IP Scanner is a cross-platform port and IP scanner that could save you a lot of time if, for example, you’ve forgotten the IP address of a device on your network. Or if you’re trying to troubleshoot a a service running on one of your computers. Or if you’re just wondering what else is connected to your network.
The first step is to download the appropriate version for your operating system from this page. The application is developed in java, so it is cross platforms compatible and works with Windows, Mac and Linux. Do keep in mind that this guide is written for Windows, but all that is said here should apply to the other versions. Also, do note that you will need to have Java installed (for the Windows version, it should just run on the Mac, and Linux has some other dependencies).
When you first open Angry IP Scanner, you will likely be asked if you want to find out how to get around the limitations of certain versions of Windows in order to increase scanning speed. Unless you are running a version of Windows earlier than Vista SP2, you need not worry as any connection limitations have been removed.
After this initial window, there will a short list of steps that explain some basic terminology and how the program itself works.
Basic subnet scan
Let’s assume you want to scan your local network to see what devices are connected. The IP entered in by default will be that of your own PC. To scan your subnet, simply change the last digit in the first IP sequence to 1, and the last digit of the second IP sequence to 255 and click Start. A list of results will show up as per below.
IP’s that respond will show up with blue icons, and you’ll also see pingtime and hostname details.
Port-scanning
If you want to scan ports within a range or just for a specific IP, Angry IP Scanner can do that too! Click on the little tool icon at the end of the first row as per the image below.
Then select the ports tab, and in the text box at the bottom, enter the port range you wish to scan, as per the image below. So to scan from ports 10-100, you simply type in 10-100.
Click OK, then click Start. The scan will run and any open ports will show up in the ports column as per the image below. You need not scan a single IP with this – you can run a port scan on a whole range of IPs. Very powerful if you want to check your network for security holes.
Other neat features
Angry IP Scanner has some other cool features, such as the ability to give you an IP from a given hostname, simply by entering the hostname (it can be a local workgroup hostname or a domain name) and click the little IP button next to it, as per the image below. The IP address will then appear in the box above.
Angry IP Scanner also allows you to export your results by clicking the Scan menu then Export all (or Export selection). There are also a number of tools directly available from the Commands menu, as shown in the screenshot below. These will launch various built-in Windows tools such as ping, traceroute and so on. It also has a few more advanced features not covered in this article, but does have a useful website full of documentation.
Also “Driver Booster Pro License Key” contain huge online data base that contain driver for every computer. Serial do drive booster 3. It support all drivers like Wi-Fi, Ethernet, Audio Driver, Video Driver, Graphic, Sound, Network, Bluetooth, USB, Any external drive and Keyboard/mouse driver etc. After scanning you just need to press scan button it will update all driver automatically.
Windows Port Scan
Conclusion
All in all, Angry IP Scanner is a very useful little utility that can potentially save you a lot of time if you have a network at home or in your office.
The Complete Windows 10 Customization Guide
In this ebook we’ll be exploring the multitude of options to fully customize Windows 10. By the end of this ebook you’ll know how to make Windows 10 your own and become an expert Windows 10 user.
Related
Introduction
Networking is an expansive and overwhelming topic for many budding system administrators. There are various layers, protocols, and interfaces, and many tools and utilities that must be mastered to understand them.
This guide will cover the concept of 'ports' and will demonstrate how the nmap program can be used to get information about the state of a machine's ports on a network.
Note:This tutorial covers IPv4 security. In Linux, IPv6 security is maintained separately from IPv4. For example, 'nmap' scans IPv4 addresses by default but can also scan IPv6 addresses if the proper option is specified (nmap -6).
If your VPS is configured for IPv6, please remember to secure both your IPv4 and IPv6 network interfaces with the appropriate tools. For more information about IPv6 tools, refer to this guide: How To Configure Tools to Use IPv6 on a Linux VPS
What Are Ports?
There are many layers in the OSI networking model. The transport layer is the layer primarily concerned with the communication between different services and applications.
This layer is the main layer that ports are associated with.
Port Terminology
Some knowledge of terminology is needed to understand port configuration. Here are some terms that will help you understand the discussion that will follow:
Port: An addressable network location implemented inside of the operating system that helps distinguish traffic destined for different applications or services.
Internet Sockets: A file descriptor that specifies an IP address and an associated port number, as well as the transfer protocol that will be used to handle the data.
Binding: The process that takes place when an application or service uses an internet socket to handle the data it is inputting and outputting.
Listening: A service is said to be 'listening' on a port when it is binding to a port/protocol/IP address combination in order to wait for requests from clients of the service.
Upon receiving a request, it then establishes a connection with the client (when appropriate) using the same port it has been listening on. Because the internet sockets used are associated with a specific client IP address, this does not prevent the server from listening for and serving requests to other clients simultaneously.
Port Scanning: Port scanning is the process of attempting to connect to a number of sequential ports, for the purpose of acquiring information about which are open and what services and operating system are behind them.
Common Ports
Ports are specified by a number ranging from 1 to 65535.
Many ports below 1024 are associated with services that Linux and Unix-like operating systems consider critical to essential network functions, so you must have root privileges to assign services to them.
Ports between 1024 and 49151 are considered 'registered'. This means that they can be 'reserved' (in a very loose sense of the word) for certain services by issuing a request to the IANA (Internet Assigned Numbers Authority). They are not strictly enforced, but they can give a clue as to the possible services running on a certain port.
Ports between 49152 and 65535 cannot be registered and are suggested for private use.
Because of the vast number of available ports, you won't ever have to be concerned with the majority of the services that tend to bind to specific ports.
However, there are some ports that are worth knowing due to their ubiquity. The following is only a very incomplete list:
- 20: FTP data
- 21: FTP control port
- 22: SSH
- 23: Telnet <= Insecure, not recommended for most uses
- 25: SMTP
- 43: WHOIS protocol
- 53: DNS services
- 67: DHCP server port
- 68: DHCP client port
- 80: HTTP traffic <= Normal web traffic
- 110: POP3 mail port
- 113: Ident authentication services on IRC networks
- 143: IMAP mail port
- 161: SNMP
- 194: IRC
- 389: LDAP port
- 443: HTTPS <= Secure web traffic
- 587: SMTP <= message submission port
- 631: CUPS printing daemon port
- 666: DOOM <= This legacy FPS game actually has its own special port
These are just a few of the services commonly associated with ports. You should be able to find the appropriate ports for the applications you are trying to configure within their respective documentation.
Most services can be configured to use ports other than the default, but you must ensure that both the client and server are configured to use a non-standard port.
You can get a short list of some common ports by typing:
It will give you a list of common ports and their associated services:
We will see in the section about nmap how to get a more complete list.
How To Check Your Own Open Ports
There are a number of tools that can be used to scan for open ports.
One that is installed by default on most Linux distributions is netstat.
You can quickly discover which services you are running by issuing the command with the following parameters:
This shows the port and listening socket associated with the service and lists both UDP and TCP protocols.
Install Nmap
Part of securing a network involves doing vulnerability testing. This means trying to infiltrate your network and discover weaknesses in the same way that an attacker might.
Out of all of the available tools for this, nmap is perhaps the most common and powerful.
You can install nmap on an Ubuntu or Debian machine by entering:
One of the side benefits of installing this software is an improved port mapping file. You can see a much more extensive association between ports and services by looking in this file:
Besides having almost 20 thousand lines, this file also has additional fields, such as the third column, which lists the open frequency of that port as discovered during research scans on the internet.
How To Scan Ports with Nmap
Nmap can reveal a lot of information about a host. It can also make system administrators of the target system think that someone has malicious intent. For this reason, only test it on servers that you own or in situations where you've notified the owners.
The nmap creators actually provide a test server located at:
This, or your own VPS instances are good targets for practicing nmap.
Here are some common operations that can be performed with nmap. We will run them all with sudo privileges to avoid returning partial results for some queries. Some commands may take a long while to complete:
Scan for the host operating system:
Skip network discovery portion and assume the host is online. This is useful if you get a reply that says 'Note: Host seems down' in your other tests. Add this to the other options:
Specify a range with '-' or '/24' to scan a number of hosts at once:
Scan a network range for available services:
Scan without preforming a reverse DNS lookup on the IP address specified. This should speed up your results in most cases:
Ip Scan For Open Ports On My Network
Scan a specific port instead of all common ports:
To scan for TCP connections, nmap can perform a 3-way handshake (explained below), with the targeted port. Execute it like this:
To scan for UDP connections, type:
Scan for every TCP and UDP open port:
A TCP 'SYN' scan exploits the way that TCP establishes a connection.
To start a TCP connection, the requesting end sends a 'synchronize request' packet to the server. The server then sends a 'synchronize acknowledgment' packet back. The original sender then sends back an 'acknowledgment' packet back to the server, and a connection is established.
A 'SYN' scan, however, drops the connection when the first packet is returned from the server. This is called a 'half-open' scan and used to be promoted as a way to surreptitiously scan for ports, since the application associated with that port would not receive the traffic, because the connection is never completed.
This is no longer considered stealthy with the adoption of more advanced firewalls and the flagging of incomplete SYN request in many configurations.
To perform a SYN scan, execute:
A more stealthy approach is sending invalid TCP headers, which, if the host conforms to the TCP specifications, should send a packet back if that port is closed. This will work on non-Windows based servers.
You can use the '-sF', '-sX', or '-sN' flags. They all will produce the response we are looking for:
To see what version of a service is running on the host, you can try this command. It tries to determine the service and version by testing different responses from the server:
There are many other command combinations that you can use, but this should get you started on exploring your networking vulnerabilities.
Conclusion
Understanding port configuration and how to discover what the attack vectors are on your server is only one step to securing your information and your VPS. It is an essentail skill, however.
Discovering which ports are open and what information can be obtained from the services accepting connections on those ports gives you the information that you need to lock down your server. Any extraneous information leaked out of your machine can be used by a malicious user to try to exploit known vulnerabilities or develop new ones. The less they can figure out, the better.