Wireshark is a open source Network Protocol Analyzer under GNU License.

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37
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4answers
147k views

How to filter http traffic in Wireshark?

I suspect my server has a huge load of http requests from its clients. I want to measure the volume of http traffic. How can I do it with Wireshark? Or probably there is an alternative solution using ...
32
votes
2answers
57k views

How to make wireshark filter POST-requests only?

How to make wireshark filter POST-requests only?
30
votes
3answers
2k views

ISP broadcasting all IP-packets, so I can see traffic of other clients from ISP

Recently I wondered why my router shows a constant downstream of 5 MBit/s, while I am downloading almost no data. I discovered the "packet logging" function of my router, with which I was able to log ...
19
votes
2answers
1k views

What's the Wireshark packet receiving and processing procedure on a Windows machine?

I am about to use Wireshark for some traffic monitoring on my Windows computer. While working on it, I was wondering how Wireshark manages to catch low level network packets before Windows does. ...
19
votes
5answers
34k views

How can I sniff the traffic of remote machine with wireshark?

I can sniff the traffic of my local pc but I would like to know how to I sniff the traffic of a remote machine by wireshark? When in capture option I select remote interface and enter my remote ip ...
19
votes
4answers
56k views

How can I filter https when monitoring traffic with Wireshark?

I want to observe the HTTPs protocol. How can I use a Wireshark filter to do that?
18
votes
4answers
92k views

What causes duplicate ACK records?

We're reviewing Wireshark captures from a few client machines that are showing multiple duplicate ACK records which then triggers retransmit and out-of-sequence packets. These are shown in the ...
17
votes
4answers
8k views

Change protocol associated with port in wireshark

I'm trying to monitor some web traffic using wireshark. Our web proxy is on port 9191. How can I get the wireshark view to treat port 9191 just like port 80 - ie as HTTP. Just using Decode_As on the ...
14
votes
5answers
27k views

Is there a way to get wireshark to capture packets sent from/to localhost on Windows?

Is there a way to get wireshark to capture packets sent from/to localhost? When I monitor traffic going from my computer to another, or from another computer to my computer, then it works. But ...
14
votes
3answers
18k views

Stopping the WinPcap Packet capture service

I just installed WireShark, which also installed WinPcap. During the installation it said "do you want xxx to start automatically", which I answered yes. Now I would like to stop the service when I ...
10
votes
1answer
8k views

Unable to open WireShark in CentOS 6.5

I have installed WireShark in CentOS 6.5 with the following packages using Yum. Dependencies Resolved ================================================================================ Package ...
10
votes
2answers
15k views

How can I search the info column in WireShark?

WireShark | Windows I want to search a packet capture of SMTP traffic for specific addresses/messages. Normally, I just sort the info column and browse but it would be nice if I could just run a ...
9
votes
4answers
42k views

How do i convert wireshark capture files to text files?

How can I convert wirshark captures (.cap) files to text files or some format from which I can read the file and parse its contents ? Regards, Mithun
8
votes
3answers
23k views

How do I install Wireshark in Red Hat Linux?

How do I install Wireshark in Red Hat Linux? At the Wireshark download page, am I supposed to download "Standard package" for Red Hat under "Third-Party Package"? Does the Red Hat version have a GUI?...
8
votes
4answers
17k views

Can Wireshark read data being sent to/from other computers?

Let's say WireShark is installed on computer A. And let's say I am looking at a Youtube video on the computer B. Can WireShark see what computer B is doing?
8
votes
1answer
21k views

Wireshark Display Filter protocol==TLSV1? (and PacketLength)

What would the filter expression be to just select the protocols where the protocol = TLSV1? Something obvious like protocol == "TLSV1" or TCP.protocol == "TLSV1" is apparently not the right way. ...
7
votes
4answers
19k views

isolate application and check what packets it is sending over the internet

I am not sure that this sort of question is appropriate here, so forgive me if I'm wrong. Here is a problem: I want to see what a specific program is sending to the internet, but the thing is that on ...
7
votes
1answer
29k views

Why does WireShark think this frame is a TCP segment of a reassembled PDU

Please find a small pcap file here illustrating my problem. I have a three-way TCP handshake, followed by two FIX logons. (FIX is a protocol used in trading.) The first FIX logon (frame 4) is ...
7
votes
1answer
10k views

How to filter for HTTP 500 responses and their requests in Wireshark?

How do I filter for HTTP 500 responses and their requests in Wireshark? I'm able to use http.response.code == 500 to find all the responses which got the return code 500 but I want to be able to see ...
7
votes
2answers
4k views

tcpdump: snaplen set to 0 but still get “Packet size limited during capture”?

Due to this problem, I'm going to sniff some packets on the MySQL server backend to see what happens: # tcpdump -vv -s0 -c 100 -i bond0 tcp port 3306 and host 192.168.3.87 -w /home/quanta/3....
6
votes
3answers
10k views

Wireshark running on a server seeing lots of `ARP who has` with different tells

We're seeing some suspicious network activity, and when I was trying to see if it was one particular server of ours I ran a Wireshark trace. I noted a lot of ARP packets asking who has x.x.x.x, but ...
6
votes
1answer
3k views

tcpdump filter for tcp zero window messages

Is there a pcap filter for TCPDump that will allow be to filter zero window messages? I know how to filter these in a wireshark display filter (tcp.analysis.zero_window) but the amount of data I ...
6
votes
2answers
8k views

No interface available for Wireshark running on Ubuntu with wireless connection

I'm completely new to wireshark. I have Ubuntu on a Dell with wireless connection. When I go to Wireshark Capture Option, I cannot select any interface since no interface is listed. What is the ...
6
votes
2answers
4k views

How to decrypt IKVe2 in Wireshark using StrongSwan log info?

Wireshark has the ability to decrypt IKEv2, if you do Preferences, select ISAKMP, it offers an IKEv2 decrypt table which wants the initiator's and responder's SPIs, the encryption and authentication ...
6
votes
2answers
267 views

TCP acks are paused, then resumed, then paused again. Why?

I would like some help finding the reason for the reduced data transfer rate in my application. I have 12 embedded systems and a Linux server. The embedded systems send data to the server over TCP on ...
5
votes
6answers
5k views

Does Wireshark pose a threat when installed on a server in the DMZ?

If you install wireshark on a web server sitting in the DMZ, is there a hack that can be used to get backdoor entrace to that server even when RDP is disblaed? I'm trying to monitor the wire on the ...
5
votes
2answers
6k views

Why my laptop sends ARP request to itself?

I have just started to learn about protocols. While studying the packets in wireshark, I came across a ARP request sent by my machine to my own IP. Here is the details of the packet : No. Time ...
5
votes
5answers
15k views

How to capture Wireshark packets when using a switched network in Windows

I’ve been asked by our SIP trunk provider to run a Wireshark trace on the network when we receive calls. The issue I’m having is that if I run Wireshark from a laptop plugged into the main switch I ...
5
votes
2answers
631 views

Is it possible for Wireshark to drop packets purposely?

I would like to test something like VoIP. I would like to test with some "artificial packet loss". Is Wireshark able to do this? Or is there any good solutions?
5
votes
2answers
2k views

Filter tcpdump file AFTER capturing

I captured a really big tcpdump file which now always crashes my wireshark. It was captured with no filters and I need to apply some afterwards to make the file smaller. Is this somehow possible?
5
votes
2answers
3k views

Silently start Wireshark

I have a computer in our office that always gets infected by viruses. Because of this, I would like to use Wireshark (or at least something) to monitor internet traffic for a while on this machine. ...
5
votes
1answer
3k views

Can WireShark detect Ethernet PAUSE packets on network when running on Windows?

We have a Windows server which is connected to a switch processing a large quantity of data. We noticed that when we disabled FlowControl on the network adapter, that it appeared that we were getting ...
5
votes
2answers
548 views

How can I easily locate a specific TCP conversation in two separate (and large) packet captures using wireshark?

Occasionally, I'll need to compare packet captures (usually wireshark or tcpdump) that are collected from both sides of a TCP conversation. Sometimes the two hosts involved are very "chatty" so I'll ...
5
votes
1answer
3k views

Client not getting address from some DHCP server

I'm working on some embedded devices which should be connected to a large network (hundreds of devices) via ethernet and that should be configured using the DHCP protocol. What I'm experiencing is ...
5
votes
1answer
260 views

What is “Cisco STG” and why would it dynamically replace a wildcard certificate on port 5061?

I have a lync client that is connecting to a Lync Edge server on port 5061. I get an invalid certificate error when connecting. When I run wireshark, during the TLS setup, and inside the ...
5
votes
2answers
2k views

syn/ack sequence number confusion

I was looking at some random traffic in wireshark and came across this (using relative seq/ack numbers): 1. myIP -> 74.125.227.96 [SYN] seq=0 2. 74.125.227.96 -> myIP ...
5
votes
4answers
6k views

Capturing multicast data with Wireshark with IGMP Snooping Enabled at the switch

I am trying to capture multicast traffic via Wireshark (actually TShark), however the switch has IGMP snooping enabled and will only send Multicast traffic on the ports that have an active IGMP ...
5
votes
3answers
335 views

What causes a switch port to receive data not destined for it?

We are having an intermittent fault which is effecting one of our control systems on one of our HP Procurve switches. For some reason, this PLC (10mbit port - 192.168.6.56) which is attached directly ...
4
votes
5answers
10k views

Wireshark filter to only capture Incoming Packets?

I am trying to setup a Filter (so my log files aren't massive) that will capture only incoming traffic. I have looked on http://wiki.wireshark.org/CaptureFilters but so far have been unable to find a ...
4
votes
3answers
616 views

determining what ports a program uses

I'm trying to use wireshark to determine what ports a certain program uses. The program connects to the server fine if we are on the same network, but I obviously need to forward the ports on the ...
4
votes
4answers
13k views

How to use sniffer to troubleshoot SMTP traffic?

We're having an issue where we are no longer receiving external emails. (We have an Exchange mail system, with a Barracuda spam filter and Watchguard hardware firewall.) The problem is that mail ...
4
votes
2answers
1k views

Why is Wireshark not capturing certain POST requests?

If I use this filter in Wireshark: http.request.method == "POST" and use the vote buttons to vote for a stack exchange question, then Wireshark captures the corresponding POST request. I can also see ...
4
votes
3answers
10k views

Sniffing the Vmware vmnet1 network with Wireshark

I have a virtual machine deployed in vmware fusion which is communicating with the host over the interface vmnet1. Unfortunately, wireshark does not offer me to to listen on that interface. Is there ...
4
votes
1answer
723 views

SSL Packet inspection on Linux

I'm trying to build a web client for an HTTPS website. I think I've done everything right, yet obviously I get a different result in the browser than with my crawler. As far as I understand, there is ...
4
votes
3answers
36k views

Excessive 'TCP Dup ACK' & 'TCP Fast Retransmission' causing issues on network. What's causing this?

I'm getting excessive TCP Dup ACK and TCP Fast Retransmission on our network when I transfer files over the MetroEthernet link. The two sites are connected by one sonicwall router, so the sites are ...
4
votes
1answer
597 views

how to view hostnames in traffic entering my webserver (Apache)?

Is there any way I can view the hostnames used by incoming traffic that is accepted by my apache webserver? For example, say the webserver is set up to process incoming traffic for an IP address, ...
4
votes
2answers
13k views

How to debug “HTTP request sent, awaiting response”?

I have a Linux server on an ADSL connection, and I just noticed that sometimes I get Connecting to example.com|xxx.xxx.xxx.122|:80... connected. HTTP request sent, awaiting response... when I use ...
4
votes
4answers
4k views

Wireshark and IPSec

I am trying to troubleshoot communication between two servers on a Windows network where IPSEC is encrypting everything. I installed wireshark on the source server and captured traffic at the point ...
4
votes
3answers
2k views

TCP segments of an HTTP Request in wrong order

My web-services server sometimes does not receive correct HTTP requests and returns "500 - Internal Server Error". Using tcpdump and Wireshark on the server, I found out that HTTP requests are ...
4
votes
2answers
12k views

Best way to analyze pcap files from Wireshark?

I've got 50-100MB pcap files captured from Wireshark and need to analyze where most of the traffic is going to/coming from. What's the best way of doing this? Ideally I'd like to end up with an ...