Wireshark Capture Filter Command Line
In this section we will look at Wireshark command line. The program which handles the interface is called a command-line interpreter or command-line processor. Wireshark. It is previously named as Ethereal. You will learn how to use the command line and the Wireshark GUI to capture packets by employing filters. If that doesn't suit you, our users have ranked 49 alternatives to Wireshark and many of them are available for Windows so hopefully you can find a suitable replacement. This is the format supported by Dumpcap for capture filters. exe, as follows. I looked in the documentation and saw something like "wireshark -f host [ipaddress]" should work but appearently my boss says it brings up a file open dialog box. This is a great way to learn how to write filter expression in Wireshark. At the upper left of the Wireshark window, in the "Filter" bar, delete the "udp" filter and type tcp. This course covers how to use Wireshark for deep packet analysis, capturing, and forensics. What to turn in 1. Wireshark can be used for network troubleshooting, analyzing, software & communication protocol development & also for education purposed. By using the filter above, you can gather only GETs with valid, new content responses. Wireshark has a command line utility. Check Point's FW Monitor is a powerful built-in tool for capturing network traffic at the packet level. Wireshark is one of the best tool used for this purpose. That said, if you know the order of the saved capture filters in the cfilters file, you can grab the matching line number of the filter you want using something like follows, and here I'm assuming that the filter you want is the 9th entry in the file:. It offers live network packet capture and offline analysis. Securing Traffic Captures. (1) Introduction. pcap The reason I'm using the command line is that wireshark requires filters are different of capture filters. This tutorial is based on these. I have written a batch file that runs a tshark command to filter fields from a wireshark pcap file and write them to a csv file. It generates Capture files in gzip format, which is easily decompressed. I typically capture traffic using the Linux command line tool 'tcpdump' but like to use Wireshark for evaluation. The most reliable and lightweight tool I know is the one made by Microsoft, a. - Wireshark crashes when using the VoIP player. tshark filters in Centos 7. Wireshark can be used to isolate and troubleshoot network and system problems, and we have flipped open the hood and taken a look into its inner workings. Using Wireshark Command Line Tools & Scripting HANDS-ON LABGUIDE Case 5 : use the tshark -z options (use file mail. By using the filter above, you can gather only GETs with valid, new content responses. The quick way to bring up this dialog box is the “ctrl-f” keyboard shortcut. Dumpcap (Wireshark) 3. The main problem here is that you may end up with a file so big that most carving tools cannot process it anymore. 9, “Filtering while capturing”. You can run some commands in the WireShark command line to solve the preceding problem. – rnxrx Dec 19 '16 at 5:40. For example in the first screen capture, I used "head -20" to print the first 20 lines of output. exe file launches the GUI version you're familiar with, but you can also launch Wireshark from the command line with a number of parameters; type Wireshark -h for a list of options and/or create shortcuts to launch Wireshark with any of those options. There are quite a few python packet parsing modules, this one is different because it doesn't actually parse any packets, it simply uses tshark's (wireshark command-line utility) ability to export XMLs to use its parsing. I’d like to take a moment to talk about Capture Filters as well. Tshark filter commands. display filters Hot capturefilters. But this can be simplified within Wireshark by clicking on Statistics -> Conversations, where it organizes all these disparate packets into TCP sessions. Wireshark supports a large number of command line parameters. The great thing about CloudShark’s capture decode is that it supports all of the standard Wireshark display filters. The quick way to bring up this dialog box is the “ctrl-f” keyboard shortcut. Capture This menu allows you to start and stop captures and to edit capture filter Analyze contains items to manipulate display filters, enable or disable the dissection of protocols, configure user specified decodes and follow a TCP stream Statistics contains items to display various statistic windows, including. With Wireshark, you tell it to capture traffic from your network card, and it can then capture any traffic going through that network. This is a windows bat file to be used in conjunction with a WLANPi device. exe) to capture the icmp traffic. The book starts by outlining the benefits of traffic analysis, takes you through the evolution of Wireshark, and then covers the phases of packet analysis. This short tour assumes you have installed the latest version of USBPcap and Wireshark 1. In Kali, I'm running wireshark, and while I'm able to see the packets that are being streamed to the VM from my router, my problem is that when I use any capture filter (ex: host 10. Merge all capture files together first with mergecap (also part of the Wireshark command line tool set) and carve the flow you need from the big merged file. However, it is still possible to use mstpcap to capture the Serial Port stream, which packetize it into a file. The former is a versatile pcap editor which can filter or split a pcap file in various fashions. If this option is provided on the installer command line, it will be passed to the Npcap uninstaller when doing an upgrade or replacement. Warning: keep your other network activities to the minimum for a better experience, e. What features tshark lacks is often found in other CLI tools that are bundled with Wireshark. display filter specification command menus Figure 3: Wireshark Graphical User Interface, during packet capture and analysis This looks more interesting! The Wireshark interface has five major components: • The command menus are standard pulldown menus located at the top of the window. The Wireshark. By using the filter above, you can gather only GETs with valid, new content responses. I just added a section on the use of -T/-e parameters after writing this blog. If the capture filter expression is not set specifically,the default capture filter expression is used if provided. I have written a batch file that runs a tshark command to filter fields from a wireshark pcap file and write them to a csv file. When reading from a pipe BPF isn't involved so something in userspace (libpcap?) would have to re-implement the filtering. You'll gain a better understanding of what happens when you tap into the data stream, and learn how to personalize the Wireshark interface. Module 9: Use Command-Line Tools to Capture, Split, and Merge Traffic. 202 but if I try to add anything extra ( for example src host 10. Filter String: broadcast and multicast. New versions of Wireshark usually become available every 4 to 8 months. Wireshark is free software, and is available for Linux, Use filters to capture only packets of interest to us ! Command line based [for the geeks in you!]. Wireshark Obtain and run wireshark on a system where you are able to capture packets. pcap in a format compatible with Wireshark. - Not possible to stop a capture with invalid filter. What features tshark lacks is often found in other CLI tools that are bundled with Wireshark. Takes only a few minutes of reading the parameters to learn how to use it. 2 Capturing with tcpdump. the full path of the dumpcap binary. I would like to add a line to decrypt the main file before filtering and save it in a decrypted format. A Word of Thanks. First, we need to install TCPdump. org You can start Wireshark from the command line, but it can also be started from most Window managers as well. Posts will be tagged with one of three difficulty levels:. Suppose there. Clear your browser cache. port == 80). Download and Install Wireshark. This package allows parsing from a capture file or a live capture, using all wireshark dissectors you have installed. Capture Filters and Display Filters. To use one of these existing filters, enter its name in the Apply a display filter entry field located below the Wireshark toolbar or in the Enter a capture filter field located in the center of the welcome screen. Convert Kismet NetXML capture to CSV; Install KDE System Sounds; Install KDE Network Manager Widget; Check Linux Kernel version; Remove spaces in string in bash variable; Check Access Logs for website; How to Connect to a remote MySQL Database; Tags. , if no -r option was specified) and a read filter if a capture file is being read (i. Plugs & extensions enable the user to use more custom features. If this option is provided on the installer command line, it will be passed to the Npcap uninstaller when doing an upgrade or replacement. After doing. By using a tool such as Wireshark, one can obtain microscopic or detailed information about the communication occurring on either your network or even an individual system (wireshark. Add Wireshark to your path 2. 1 and host 10. • Start up the Wireshark packet sniffer, and begin Wireshark packet capture. It also covers basics behind measuring network performance and tools to use such as bmon and iperf. Say your XP IP address is 192. We’ll review some of the command line tools and outline how to download and install Wireshark on either a PC or MAC. echo "* menushark script also gives you the command that the menu system has *" echo "* made to try to teach you how to use tshark at the command line. This issue may occur if the network traffic is captured before the checksum is calculated. But you might not get the latest package for Wireshark using this method. Use ipconfig to display the default gateway address. Wireshark Starter. What command can Jennifer use? What is the generic syntax of a Wireshark filter? The command-line equivalent of WinDump is known as. Before a capture point is activated, some functional checks are performed. Wireshark is a network protocol analyzer that can be installed on Windows, Linux and Mac. pcap file can be halted manually or configured with time or packet limits, after which the capture point halts automatically. cap) a)Create a protocol hierarchy with '-qz io,phs', which protocols are present. Wireshark Filter Toolbar. You can use both capture filters and display filters with tshark but they are different command line switch options: capture filter example: tshark -f "not port 22" display filter. Tshark bears resemblance to tcpdump in that it is a command-line only tool. I looked in the documentation and saw something like "wireshark -f host [ipaddress]" should work but appearently my boss says it brings up a file open dialog box. Mastering Wireshark Display and capture filters in CLI Networking Command Line Tools Tutorial: Packets don't lie: how can you use tcpdump/tshark (wireshark) to prove your point. in Wireshark, if you're starting the capture from the GUI, select "802. In this section we will look at Wireshark command line. 2) for the interface that is connected to the internet and put that after the -i parameter below:. This Wireshark Advanced Technologies course, taught by bestselling author and trainer Robert Shimonski, features nearly 11 hours of training and is designed to provide network administrators with the practical skills needed to solve problems, analyze data, view the inner workings of packets, and perform advanced config. 2, "The system specific "Save Capture File As" dialog box" shows some examples of this dialog box. We can start a very basic packet capture by invoking dumpcap with the command below. Final command to capture. DISPLAY FILTER SYNTAX For a complete table of protocol and protocol fields that are filterable in Wireshark see the wireshark-filter(4) manual page. LEARN MORE Wireshark - How To Capture, Filter , Inspect Network Packets?. 0 through 4. This will create a few output files, including audio, noting videosnarf does not support AAC, so for testing purposes, I've disabled it by using the capset filter on the C40 endpoint. Wireshark supports a large number of command line parameters. The argument to -i will vary according to your setup. - Malformed packet with IPv6 mobility header. Without any options set, TShark will work much like tcpdump. This is good, as you only have to learn one syntax for both tools. 1/8/2018 0 Comments is a network packet analyzer that works within the command line, and is. The FW Monitor utility captures network packets at multiple capture points along the FireWall inspection chains. Thanks reddit!. 8, the capture filter box is present directly on the options screen, but on Wireshark 1. Use dumpcap (part of the Wireshark suite) on the command line to setup a capture into a set of capture files (so that you don't end up with one huge unworkable file). cap) a)Create a protocol hierarchy with '-qz io,phs', which protocols are present. This week's post provides a brief introduction to wireshark and shows two basic filters that can be used to extract two different classes. After a Wireshark capture point has been defined with its attachment points, filters, actions, and other options, it must be activated. Finally, the book focuses on packet analysis for security tasks, command-line utilities, and tools that manage trace files. Wireshark can be used to isolate and troubleshoot network and system problems, and we have flipped open the hood and taken a look into its inner workings. Making a Telnet. All Access Pass Members: The Tshark Command-Line Capture course is released on the new portal. It provides a comprehensive capture and is more informative than Fiddler. What command can Jennifer use? What is the generic syntax of a Wireshark filter? The command-line equivalent of WinDump is known as. For more information on dumpcap consult your local manual page (man dumpcap) or the online version. echo "* menushark script also gives you the command that the menu system has *" echo "* made to try to teach you how to use tshark at the command line. User’s guide is very important especially for beginners. > Wireshark doesn't work. Place your test call, and then hit CTRL-C from the command line to exit the capture. So, if you need to do it from the command line, use tshark. As seen in Figure Wireshark Capture View, a list summarizing the packets in the capture file will be shown in the top list, with one packet per line. hSenid Lanka: Wireshark 14 • It is cross-platform. Final command to capture. Before a capture point is activated, some functional checks are performed. The Applying Filters to TCPDump and Wireshark lab teaches students how to apply a capture filter to TCPDump and Wireshark using Berkley Packet Filter (BPF) Syntax. Type the packet capture command, such as:. To see what they are, simply enter the command wireshark -h and the help information shown in Example 9. In this section we will look at starting it from the command line. Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. 9, you set a capture filter by double-clicking on the interface. It generates Capture files in gzip format, which is easily decompressed. The tool Wireshark is a fantastic tool for both capturing traffic and evaluating traffic. It also has the same powerful analysis capabilities as Wireshark and uses the same type of filtering. 24 appears in the packet source. Without any options set, TShark will work much like tcpdump. o Configure Wireshark o Save, open, import & export capture files o Capture & display filters o Colouring rules o Find specific packets o Timestamps o Graphs & flowcharts o Profiles o Remote capture o Context sensitive menu o Decode VoIP calls Filters o Capture filters. For instructor-led Windows Server training, see our class schedule. 32MB; 5 - Introduction to Wireshark Command Line Interface and Tshark/20 - Difference between display and capture filters in CLI. So the full command line would be tcpdump -r original_pcap_file -w new_pcap_file -s 0 capture_filter_expression. Wireshark is an open source protocol analyser, commonly used among the network and security professionals. Both tshark and tcpdump use the pcap library, so the capture filters use pcap-filter syntax. The second provides a quick reference for some of the more common Wireshark display filters. pcap , where editcap is included in the Wireshark installation, capture. Wireshark will automatically stop capturing, and you can save the capture file or play around with it. • “Understands” the structure of different network protocols. Of interest to us now are the File and Capture menus. For example in the first screen capture, I used “head -20” to print the first 20 lines of output. The GUI is the most common technique used by network analysts, but those who want to capture from scripts or simply don't want to work through the GUI use Tshark or Dumpcap. Wireshark is a protocol analyser available for download. I then rely on filters post capture to parse out unneeded data. The topics that will be covered in this chapter include:. > Where can I find documentation about the USBPCapCMD command line arguments? Standard command line parameters are: -d is used to specify USBPcap filter device name. 1, “Help information available from Wireshark” (or something similar) should be printed. In short, even if a Windows client application is configured to use DSCP 46 (EF), for example to mark voice traffic, it will translate this over the air to to use a layer 2 UP value of 5, rather than 6. How to Filter by IP in Wireshark Using a Capture Filter Up to this point we've only been talking about Display Filters, which are the filters applied post capturing packets. Capture Filters. It provide many useful commands and capture filters that can be used on terminal which provides an efficient way to analyse the incoming traffic and capture the traffic in pcap. Type telnet gmail-smtp-in. Wireshark Commands. This will capture all port 110 traffic and filter out the "user" command line and save it to a txt file. cap file from the command line. - Use filter "udp&&boot. Without any options set, TShark will work much like tcpdump. With Wireshark, you tell it to capture traffic from your network card, and it can then capture any traffic going through that network. The filter expression is also shown in the marked section of the screenshot below. A sample tshark capture command goes as follows (say you want to monitor the interface eth0): sudo tshark -i eth0 We can add capture filters along with the command as well: sudo tshark -i eth0 "port 6633". 11 Sniffer Capture Analysis -Wireshark filtering. tshark is a packet capture tool that also has powerful reading and parsing features for pcap analysis. Capture filters are added prior to commencing an over the air capture with Wireshark, as shown in the screen-shot below (see green highlighted text): ( Note that if the capture filter text is highlighted in red (rather than the green shown above), then there is an issue with your filter that needs fixing. • “Understands” the structure of different network protocols. By default “head” will show the first 10 lines of output but you can modify this as needed, feeding it the number of lines you want to see as a command line switch. 1rc0-10-g22e7952e06f0) Capture network packets and dump them into a pcapng or pcap file. Introduction Ethanalyzer is a Cisco NX-OS protocol analyzer tool based on the Wireshark (formerly Ethereal) open source code. Wireshark color codes the background as you type to alert you to capture filter errors. To view only ICMP traffic, type icmp (lower case) in the Filter box and press. 2p5 does not properly handle when a file in the current working directory has the same name as a pseudo-command in the sudoers file and the PATH contains an entry for ". Clicking on the Capture Filter option will allow you to only capture certain types of traffic, such as TCP traffic, UDP traffic, or traffic streams that operate on a specific port. com 587 instead to generate SMTP traffic and then filter on port 587 in the next activity. How to Filter by IP in Wireshark Using a Capture Filter Up to this point we've only been talking about Display Filters, which are the filters applied post capturing packets. Filter String: broadcast and multicast. dumpcap can be run independently from Wireshark to capture packets to a file or series of files on disk, and makes for an efficient long-term capture solution. Adding -A to the command line will have the output include the ascii strings from the capture. Download and Install Wireshark. A Word of Thanks. Wireshark includes filters, color coding, and other features that let you dig deep into network traffic and inspect individual packets. The easiest is to start the deamon from the command line now: rpcapd -n. 2, “Start Wireshark from the command line”. tcpdump is a command-line, low-level tool that is generally available as part of a Linux distribution's default package installation. Wireshark uses pcap to capture packets. I used this and worked well for src and dst host- C:\Program Files\Wireshark>tshark. When installing Wireshark you'll also get a tshark command, which is a command line version of wireshark. Filter by IP, protocol, exclude traffic and much more. You may also run into issues with your shell and quoting, what is your OS and shell? Can you amend your question with an example of the command line you have tried?. After the pings have been sent, minimize cmd. Help information available from dumpcap. Wireshark Capture Point Activation and Deactivation. • The ping command is in c:\windows\system32, so type either “ping –n 10 hostname” or “c:\windows\system32\ping –n 10 hostname” in the MS-DOS command line (without quotation marks), where hostname is a host on another continent. Do not worry. Finally, you will learn advanced topics, including capturing on the command line, splitting and merging capture files, and getting statistics on the command line. Its main function is to remove packets from capture files, but it can also be used to convert capture files from one format to another, as well as to print information about capture files. echo "* menushark script also gives you the command that the menu system has *" echo "* made to try to teach you how to use tshark at the command line. Capture files can be programmatically edited or converted via command-line switches to the "editcap" program. Wireshark User's Guide 27846 for Wireshark 1. Figure 4b: Wireshark Graphical User Interface for Mac OSX. A complete list of powerful wireshark display filters. Both executables are added to your PATH and can be invoked from the command line. BPF stands for Berkeley Packet Filter and is a language specifically designed for expression of network traffic as filters. Type the packet capture command, such as:. After installation, you’ll find shortcuts for mitmweb and mitmdump in the start menu. It's available on most major platforms including the main distributions of Linux (for Ubuntu for example, command-line sudo apt-get install wireshark is all that's needed. If you only care about that particular machine's traffic, use a capture filter instead, which you can set under Capture -> Options. For example in the first screen capture, I used “head -20” to print the first 20 lines of output. Wireshark User's Guide 27488 for Wireshark 1. The tack r filename option for tcpdump will display a capture file onto the screen. Capture Only HTTP traffic in tshark. Open Wireshark; Click on "Capture > Interfaces". As most folks who use Wireshark know, Wireshark comes with a collection of command line or terminal based utilities. Type Wireshark in the Run command box. I don’t know how others use it but I use to monitor the GET and POST requests that are being sent from my machine. To see what they are, simply enter the command wireshark -h and the help information shown in Example 10. Start Wireshark from the command line. Of interest to us now are the File and Capture menus. Because in situations where a bulk load of traffic is flowing on the network, Wireshark's capture engine may not be. Stop the Wireshark capture. This option is useful when capturing packets over a longer period of time. Wireshark can be used for network troubleshooting, analyzing, software & communication protocol development & also for education purposed. 12 hSenid Lanka: Wireshark 13. Fortunately,Wireshark has sophisticated analysis mechanisms that can be used for wireless traffic analysis. Check the difference between "capture filter" and "display filter" as each of them has a different syntax and purpose (while the difference in purpose is clearly visible in Wireshark but much less clearly in tshark). 2 allows local users to change the permissions of arbitrary files, and consequently gain privileges, by blocking the removal of a certain directory that contains a control socket, related to improper interaction with ksm. -h Print the version and options and exit. Capturing Traffic From Remote Computers. What are popular packet sniffers on Linux; How to filter, split or merge pcap files on Linux; How to fix Wireshark GUI freeze on Linux desktop. Capture filters are filters that are applied during data capturing; therefore, they make tshark discard network traffic that does not match the filter criteria and avoids the creation of huge capture files. Capture Filters are used to reduce the size of incoming packet capture, essentially filtering out other packets during live the packet capturing. If any of the environment variables SSH_CONNECTION, SSH_CLIENT, REMOTEHOST, DISPLAY, or SESSIONNAME are set, Wireshark will create a default capture filter that excludes traffic from the hosts and ports defined in those variables. A couple of questions have come up on the wireshark-users mailing list recently about using capture filters for MPLS and VLANs. Curl/wget to grab a webpage. tshark is a packet capture tool that also has powerful reading and parsing features for pcap analysis. 130 and dst host 192. Troubleshoot, capture, export, examine and save packets from your router to tftp, ftp, http, scp destination. This command will produce a summary of a pcap with statistics, start / finish times and other details. It also covers basics behind measuring network performance and tools to use such as bmon and iperf. Use dumpcap -D to list your network interfaces and select the number (i. If you need a capture filter for a specific protocol, have a look for it at the ProtocolReference. To quickly filter the entire capture to only commented packets, the “pkt_comment” display filter may be used. The “Capture Interfaces” dialog box. The GUI is the most common technique used by network analysts, but those who want to capture from scripts or simply don't want to work through the GUI use Tshark or Dumpcap. 6 you can append the -color option to tshark and it will print out colorized packets too!. tcpdump Command Line Tool. For example, to get all TCP packets use the expression tcp or to capture DNS packets the expression is udp port 53. - Course 8: Use Command-Line Tools to Capture, Split, and Merge Traffic. exe -f "src or dst host 192. Towards the top of the Wireshark graphical user interface, is the packet display filter field, into which a protocol name or other information can be entered in order to filter the information displayed in the packet-listing window (and hence the packet-header and packet-contents windows). display filters Hot capturefilters. Using capture filters for tcpdump. Wireshark Remote Capturing. Wireshark stores packets in the specified. Red Hat Enterprise Linux 5 CentOS Linux 5 Oracle Linux 5 The command matching functionality in sudo 1. The Applying Filters to TCPDump and Wireshark lab teaches students how to apply a capture filter to TCPDump and Wireshark using Berkley Packet Filter (BPF) Syntax. *" echo "* 2)Shows you the command line it created. New versions of Wireshark usually become available every 4 to 8 months. Most existing documentation on Wireshark focuses on the GUI. You have a quoting issue and a syntax issue. You can try telnet smtp. Without any options set it will use the pcap library to capture traffic from the first available network interface and write the received raw packet data, along with the packets' time stamps into a libpcap file. Wireshark, a network analysis tool formerly known as Ethereal, captures packets in real time and display them in human-readable format. Then, run a curl/wget to grab a webpage. To quickly filter the entire capture to only commented packets, the “pkt_comment” display filter may be used. The Filter: text entry lets you set a capture filter expression to be used when capturing. Tshark filter commands. 15 or host 192. This can be done using the -f command-line parameter, followed by a filter in double quotes. cap file, which you can find in the Wireshark Sample Captures. Now click Start. ) How to Inspect Captured Packets. Use ipconfig to display the default gateway address. Run it as below or you can use the table option -T to produce tab separated output that can be imported into a spreadsheet or parsed on the command line. It is the de facto (and often de jure) standard across many industries and educational institutions. In addition, packet capture may be incomplete and the packet capture tool may be abnormal. If the filter is specified with command-line arguments after the option arguments, it's a capture filter if a capture is being done (i. Without any options set, TShark will work much like tcpdump. The most reliable and lightweight tool I know is the one made by Microsoft, a. The first thing I want to do is open up a Command Prompt, and then we'll browse where Wireshark is. Nearly 5 Hours of Expert Video InstructionThe Wireshark Fundamentals LiveLessons video training course offers nearly 5 hours of expert instruction on using the free, open source Wireshark to troubleshoot Ethernet and Wi-Fi networks, and the protocols they transport. For example, to get all TCP packets use the expression tcp or to capture DNS packets the expression is udp port 53. Since this is a blog about IPv6,the two must useful capture filters are: ip6; icmp6; Continuing on the example above, but only capturing IPv6 traffic place the capture filter last on the command line. The argument to -i will vary according to your setup. There are a couple of ways to read a packet capture. In addition, TCPdump lends its self very well when combining packet sniffing with automation of BASH scripting. Determine which interface index maps to which NIC 3. Network Protocol Specialists » Blog Archive » Using Wireshark. Wireshark Capture Filter Command Line. 8, the capture filter box is present directly on the options screen, but on Wireshark 1. 1 –s 100 9-i 4 –p is specifically for my wireless interface 9host 10. Take our Wireshark training course so you can begin a high paying career in the field of network analysts. Online Courses > IT + Security > IT Certification. 1 is the target of my capture filter 9Only capture the first 100 Bytes. You may know the common ones, such as searching on ip address or tcp port, or even protocol; but did you know you can search for any ASCII or Hex values in any field throughout the capture? It’s true. it gives you the command line to fire the same - Ganesh R. 9, you set a capture filter by double-clicking on the interface. To access T-Shark, simply open a Terminal or command line window (in Windows Start> Run> cmd) and when the terminal opens, you will need to change directory to the Wireshark directory: Now that you are there, you will need to get the Interface numbers so you can specify which interface you want to capture on. - Wireshark crashes dissecting Profinet NRT (DCE-RPC) packet. Tcpdump prints out a description of the contents of packets on a network interface that match the boolean expression; the description is preceded by a time stamp, printed, by default, as hours, minutes, seconds, and fractions of a second since midnight. So the full command line would be tcpdump -r original_pcap_file -w new_pcap_file -s 0 capture_filter_expression. Upon firing up Wireshark first you need to choose the interface for which you want to capture the traffic for wireless, ethernet etc.