netstat -s for TCP Statistics

tbaror · 09-20-2009, 04:35 PM

Hello All,

i trying to figure out TCP Statistics especially Failed Connection Attempts .
I would like to understand what value would indicate high as threshold?.
Also i would like to know if appearing of errors of such kind indicate issue at remote host or local, and what could cause such errors ,network bandwidth or lack of IO etc..

Thanks

unSpawn · 09-22-2009, 04:21 PM

To find out what value is high or not you have to understand what the item means. You could start by running 'strace -v netstat -s'. You'll find one of the keys it reads is /proc/net/snmp. This proc key showing traffic stats is populated by whatever goes on in the kernels source .*/tcp.c (around line 700-900 in kernel 2.4.9 IIGC). You'll find it's about in-flight SYN discrepancies. But what value would be high I wouldn't know, this shows on one of my machines:

Code:

Tcp:
    7971661 active connections openings
    7104573 passive connection openings
    31224 failed connection attempts

and it definately works OK...