This is our old Q&A Site. Please post any new questions and answers at

Hello Wireshark Gurus,

I am having a problem where file transfers between two windows server machines are failing mid way sometimes when the file exceeds 1/2Gb in size.

I have attached a link that points to the pcap:

source is dst is

I am seeing errors at the end of the file and trying to explain to Microsoft has gotten me no where. Can you please take a look and assist if you can.

asked 09 Jun '14, 14:02

Sigma55's gravatar image

accept rate: 0%

edited 11 Jun '14, 04:47

grahamb's gravatar image

grahamb ♦

Looks to me like stops sending data in the middle of a 61440 byte sized data chunk. Since the other PC with IP does not receive any further data it resets the session in packet 282192, after close to 30 seconds of "silence" - probably a timeout.

Next step: capture next to to find out if it really stops sending or if the packets just do not make it through anymore.

Two tips here:

  1. Capturing on one of the affected systems isn't optimal, see
  2. Putting 300+ MB file up for download only makes sense if you really need all the payload. In your case you could probably greatly reduce the size by only capturing the first 256 bytes of each packet, which should include all SMB headers. There is an option in the capture settings where you can limit how much bytes are kept for each packet.
permanent link

answered 09 Jun '14, 14:31

Jasper's gravatar image

Jasper ♦♦
accept rate: 18%

Thank you for your quick response.

I have read the article and it sheds some light on why you shouldn't do it. Should I instead to the capture on a system connected to the same network off a switchport?

I will also look into limiting the size of the capture as you mentioned.

Feedback to follow.


(10 Jun '14, 08:01) Sigma55

Yes, capturing on an additional system connected to a SPAN port would help avoiding those problems. Of course that requires that the switch can do SPAN ports.

(11 Jun '14, 00:34) Jasper ♦♦

OK. did some more testing. turns out, that server is the only server that has problems copying the files. All the other servers can copy the files without error on the same network. I will use the SPAN port to monitor further but it seems to be a software problem.

Thank you very much for your time sir.

(12 Jun '14, 10:27) Sigma55
Your answer
toggle preview

Follow this question

By Email:

Once you sign in you will be able to subscribe for any updates here



Answers and Comments

Markdown Basics

  • *italic* or _italic_
  • **bold** or __bold__
  • link:[text]( "title")
  • image?![alt text](/path/img.jpg "title")
  • numbered list: 1. Foo 2. Bar
  • to add a line break simply add two spaces to where you would like the new line to be.
  • basic HTML tags are also supported

Question tags:


question asked: 09 Jun '14, 14:02

question was seen: 2,614 times

last updated: 12 Jun '14, 10:27

p​o​w​e​r​e​d by O​S​Q​A