# network traffic monitoring - differences between systat, glances and iftop



## huehnerhose (Sep 11, 2018)

I try to monitor my network traffic on certain servers. Since I use Linux and FreeBSD I was used to use `glances` as my "go-to-tool". When I need more detailed insights into my network traffic I used `iftop` and today I found `systat -ifstat`. My understanding so far: All these tools are capable of showing me "current network traffic in $unit". 

Running all three in parallel I was curious to see differences in traffic recorded, especially in recorded peak values. For example:


```
systat -ifstat:
           igb1  in    686.947 KB/s          2.581 MB/s           39.679 GB
                 out    51.219 MB/s        120.706 MB/s            2.635 TB
                
iftop:
TX:             cum:   33.2GB   peak:    628Mb                                          rates:    628Mb   529Mb   468Mb
RX:                     405MB           7.99Mb                                                   7.99Mb  5.36Mb  4.84Mb
TOTAL:                 33.6GB            635Mb                                                    635Mb   534Mb   473Mb

glances:

            Rx/s  Tx/s
igb1      6.99Mb  537Mb
```

As you can see: `iftop` and `glances` are roughly in the same ballpark, but `systat` allways shows values much lower. 

Can somebody give me a hint, why this could be and maybe where the differences in the measurements origins?

Thanks


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## leebrown66 (Sep 12, 2018)

bit vs byte.  Try `systat -ifstat -scale mbit`


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