Search code examples
linuxnetwork-programmingtcpnetstat

TCP data loss event

I have run the command netstat -s on a Linux server and got this line (under TcpExt) :

15115 TCP data loss events

does it mean that the data was completely lost complete or could it have been re-transmitted?

Solution

  • Take a look at RFC793 which is the RFC for TCP. It explains that TCP "guarantees" delivery in the sense that the data will be confirmed to have been delivered, or the information will exist to show that the data was not delivered.

    Within the operation of TCP the re-transmission of data can be commonplace - that's why TCP packets uses sequence and acknowledgement numbers.

    So, to answer your questions, the data would never be "completely lost", and could certainly have been transmitted at some point during the TCP session.

    Hope this helps.