Solved

exchange 2013 receive connector reject

Posted on 2015-01-01
3
129 Views
Last Modified: 2015-01-07
Hi.
I am getting the following warning in my exchange 2013 error logs:

Receive connector Internet Connector HFC-EKHAT rejected an incoming
connection from IP address 1xx.2xx.1xx.1xx.
The maximum number of connections per source (20)
for this connector has been reached by this source IP address.


This appears constantly in the logs.  This is incoming from a country that we don't usually send or receive mails from often.

Is this normal or could this point to something more sinister?

Thanks.
0
Comment
Question by:fijiboy
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
3 Comments
 
LVL 31

Expert Comment

by:Gareth Gudger
ID: 40527028
Sounds like someone is trying to perform some sort of denial of service attack. It sounds like Exchange is your first hop. Do you have any kind of message hygiene software, appliance or cloud service in front of your Exchange server? If not, I'd recommend it.
0
 

Author Comment

by:fijiboy
ID: 40527123
Thanks Gareth. We currently do not have a service in front of our email server apart from our corporate firewall. Am looking at some security for email security etc. Is there something I can do hardware the server in the meanwhile? They seem to be connecting on port 25.
0
 
LVL 31

Accepted Solution

by:
Gareth Gudger earned 500 total points
ID: 40527249
A temporary solution may be to block that IP at your firewall. But they will often change IPs so this is a temporary solution at best.

If you have the Edge Transport role in your environment you could also do an IP Block List Provider - might help.
0

Featured Post

Industry Leaders: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Scam emails are a huge burden for many businesses. Spotting one is not always easy. Follow our tips to identify if an email you receive is a scam.
In-place Upgrading Dirsync to Azure AD Connect
To add imagery to an HTML email signature, you have two options available to you. You can either add a logo/image by embedding it directly into the signature or hosting it externally and linking to it. The vast majority of email clients display l…
Exchange organizations may use the Journaling Agent of the Transport Service to archive messages going through Exchange. However, if the Transport Service is integrated with some email content management application (such as an antispam), the admini…

740 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question