High Server Traffic

[NewUser@]

Our company recently installed Plesk on our dedicated server. In looking around the various Plesk features I noticed that under Server Traffic for our main domain, the POP3/IMAP service recorded over 80 GB of traffic Used within the last 25 days.

This number seems ridiculously high to me. We're a small company with less than 30 employees and we mainly use this server to host a simple company website and handle our POP email accounts.

Is this 80GB number accurate or is there some error within Plesk that could have cause this number to be this high? Or has our server somehow been compromised by a hacker/spammer who is generating this trafffic? My immediate assessment is that the server is not compromised.

Just trying to figure out where this traffic number comes from and whether I should be concerned by it.

Any insight into this issue would be greatly appreciated.

 

[Mertz]

It's probably accurate if your users transmit a lot of large attachments. Even if your company doesn't do that on official business, you could have some users that are transferring MP3 files or video files around to each other.

 

[renhack]

Actually a better cause is if your sending bounce messages.

A spammer sends out mail with your company email for a reply to address. You get tons of bounce back messages.

Even worse, they could use a made up email address from your company, the bounce from the end mailserver comes back to an invalid email at your server triggering your server to send a bounce message back to the end server.

One of the reasons we dont bounce messages.