Member Avatar for lsutiger

Hi all! I have been scouring the net loooking for some help with a problem our company is having.
We have our own smtp/pop3 server setup in house. We are using Dyndns' mailhop service in order to control spam, and it works! When someone sends our domain an email, it is forwarded to their servers, scanned and then forwarded to our server.

But lately we have been receiving our emails anywhere from one to several hours late. I looked at the headers for a bunch of messages and they are getting from point a to point b in a timely fashion, but from point b to c is the problem.

When I contacted Dyndns' tech support, they stated that their logs show that there were connection timeouts when trying to contact our server.

My question is how to troubleshoot this problem and find the point of failure.

Thanx in advance!

  • 4 Contributors
  • 5 Replies
  • 95 Views
  • 2 Days Discussion Span
  • Latest Post Latest Post by DimaYasny
Member Avatar for malan_in

check the DNS server and MX recored, use traceroute and check the latency....

Member Avatar for DimaYasny

a good tool would be MRTG, especially if you leave it running overnight.

also see what happens if you try to send mail directly to your server - does dyndns lag in resending, or is that your server having problems after all.

Member Avatar for bobbyraw

has anyone in the company set up mail forwarding, for their account this can be a real bummer, by this i mean say i have an email yout your company, but i want to get my mails when i am at home ( you presently dont have web access) i would set my person email to grab mails from your server so i can access them through my personal mails when i am at home

Member Avatar for lsutiger

Thanx for all of the replies. I narrowed it down to our router's poor port forwarding ability. It is just a BEFSX41.

To try and curb the spam, I also was using 2525 as my external port for SMTP and 25 for my internal port. Once I changed it back to 25, the delays stopped. Is there any way I can setup the SMTP plugin only to accept connections from certain IPs? That would rock since we should only get connections from Dyndns' server.

BTW I am using WS2003, IIS 6.0 and the SMTP plugin from microsoft.

Member Avatar for DimaYasny

the easiest way is to open incoming port 25 fot the dynds IP(s) on the firewall

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.