I have been told that one of my servers intermittently throws ZeroWindow errors. I would like to monitor this in Prometheus.
If I run neststat -s some of the results are:
netstat -s
Ip:
...
IcmpMsg:
...
Tcp:
...
TcpExt:
TCPFromZeroWindowAdv: 96
TCPToZeroWindowAdv: 96
TCPWantZeroWindowAdv: 16
It is very difficult to find a definition for this the closest that I have found is:
Reading this I believe that WantZeroWindowAdv show the ZeroWindow problems. (It counts each time that a socket is requested its window size and responds with 0.)
Not part of the question - then I would need to add this to nodes_netstat.go for prometheus.
Am I correct - is this approach valid? Netstat is not highly documented.
Your descriptions of "To" and "From" are correct.
"Want" is when TCP would have liked to have sent a zero window back to a sender, but couldn't because that would have implied a shrinking of the window rather than it being full.