How can i monitor my VPS real bandwidth usage?

Question

I have a VPS that suspended for use out of bandwidth limitation. In DirectAdmin report I have no change in the use of bandwidth and all things are normal (bandwidth usage is less than 4 GB and my limitation is 250 GB), but in my server company's report VPS use about 1.5 TB of bandwidth just in 4 days!

How can I found problem when in direct admin bandwidth usage is normal and I dont install any other service in my VPS in 4-5 months ago. May I monitor my bandwidth and ports by other tools?!

SERVER DETAILS: Open VZ - Cent OS - HDD: 10 GB - BW: 250 GB/Monthly - CP:DirectAdmin - i have a root access. 1 dedicated IP.

Bandwidth Used in my Server Company Report : over 1.6 TB in 4 days.

Bandwitdth Used in my DirectAdmin Report: Lessthan 5 GB.

Answer 1

You could install a utility that counts bytes passing over the network interface, such as vnStat. Installation instructions for CentOS are here.

Note that this won't help you check how much bandwidth you used before you installed it, so you won't be able to use it to contest the figure reported by your hosting company this time.

You might consider that DirectAdmin does not log bandwidth usage for the following:

• Pop/Imap.
• Data transfers from within scripts, such as uploads/downloads done by code within a script.
• SSH level commands such as wget.
• Service updates using custombuild, yum, apt-get.
• Any low level network traffic, pings, etc.

Of those, it's possible that email and scripted file downloads/uploads may be contributing significantly to your total bandwidth figure. I suggest that you ask your hosting company to confirm where the bandwidth's being used this time, and log it yourself in future with vnStat so that you're able to contest future reports if necessary.