First time here? Check out the FAQ!

THIS IS A TEST INSTANCE. Feel free to ask and answer questions, but take care to avoid triggering too many notifications.

FTP upload is disrupted

retag add tags

Hi I am having a recurring problem when I upload a file from the maintenance server (CENTER) to a branch server The upload is suddenly interrupted half way through the file transfer

Other that a lot of retransmissions, I don't see something wrong in the pcap files

The wireshark captures, on both sides, where made connecting a windows host to a mirror port on the local switches The communications between the sites are thru a site to site VPN

Here are the captures

https://1drv.ms/u/s!AhaIf1uNR2GF8V1ua...

Thanks, in advance

lwbuyer

asked 2021-03-06 18:50:45 +0000

edit flag offensive 0 remove flag close merge delete

Comments

add a comment see more comments

1 Answer

Sort by

oldest

newest

most voted

It is not wrong, but SACK, Selective Acknowledgement, is not enabled on 10.10.250.2. So when packet loss occurs the file transfer stalls in your case and TCP slow start is triggered again.

Enable SACK when possible.

176

André

answered 2021-03-09 19:06:18 +0000, updated 2021-03-09 19:09:00 +0000

edit flag offensive 0 remove flag delete link

Comments

Thank you I am going to tray to enable it.

lwbuyer (2021-03-10 02:45:59 +0000) edit

add a comment see more comments

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account. This space is reserved only for answers. If you would like to engage in a discussion, please instead post a comment under the question or an answer that you would like to discuss.

Add Answer

FTP upload is disrupted edit

Comments

1 Answer

Comments