Ask Your Question
0

Every 5 minutes exactly I get 20 seconds of TCP Previous segment not captured

asked 2026-04-26 19:32:32 +0000

scribbledSums gravatar image

This happens whether I'm connected to my home network or to a mobile hotspot, and it only happens on my computer. I've measured it numerous times and it's always every 5 minutes with 20 seconds of this problem. Wireshark gets flooded with TCP "Previous statement not captured", "Dup ACK", "Retransmission", and "Out-of-order" and I get lots of packet loss and increased ping times (from 20-30ms to 100-200ms). I'm on Linux Mint 22.3 and I've tried nethogs and iftop but neither have shown anything out of the ordinary.

edit retag flag offensive close merge delete
add a comment

1 Answer

Sort by ยป oldest newest most voted
0

answered 2026-04-27 06:08:47 +0000

SYN-bit gravatar image

Sounds like something is generating a lot of traffic, perhaps overloading your Internet connection. If it happens every five minutes, it seems to be scheduled. You might want to check your crontab entries for an automated speedtest.

To/from which hostname/ip-address are most of the packets during those 20 seconds? That might indicate which tool is doing the speed-tests.

edit flag offensive delete link more

Comments

Sorry for replying so late and thank you for your suggestions. I do not have any crontab entries and after doing many more Wireshark captures, the previously mentioned packets do not appear anymore, yet I still get the same increased ping times. As for your question, I don't really know much about this but as far as I can tell, most of the traffic involves ip addresses that don't belong to my computer (on both source and destination) and the traffic that does involve my ip addresses is very minimal, a single packet once every few seconds. Additionally, with the "Dup ACK", "Out-of-order", etc. packets no longer appearing, the overall traffic doesn't change.

I also mentioned in my post that this happens if I'm connected to a mobile hotspot. That does not happen anymore, if it did happen at all. So it only happens on this ...(more)

scribbledSums gravatar imagescribbledSums ( 2026-04-28 00:53:32 +0000 )edit
add a comment

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Question Tools

1 follower

subscribe to rss feed

Stats

Asked: 2026-04-26 19:32:32 +0000

Seen: 34 times

Last updated: yesterday