Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Is it possible to run an email server on my home box using dynamic dns?

The scenario is, I want to auto cc all incoming and outgoing emails from my one account to another, from some server side config instead of configuring email clients for rules. I have tried Google Apps Mail but it doesn't allow auto cc of outgoing emails. After having read tons of blogs, forum messages etc (hope I have been reading the correct info :) ) the only option to achieve what I am needing is to setup my own mail server, but the cost of getting a static IP doesn't fit my budget.

Please can someone point me in the correct direction. Platform doesn't matter, I can setup a Windows or Linux server.

Many Thanks

share|improve this question

migrated from Mar 4 '11 at 15:01

This question came from our site for system and network administrators.

what are you trying to accomplish? (a) keep copies of all messages on both accounts or (2) keep copies of all messages in 1 account, but be able to send as 2 different accounts? if you are looking for (2), then gmail allows you to send as a different account and you could configured your other account to forward all messages to your gmail account. – Peter Carrero Mar 4 '11 at 19:11

Running an email server on dynamic DNS, while certainly possible, is a bad idea. Here's why:

If you don't want to get a static IP, then I'd suggest checking into the various email hosting services (google for "email hosting") and see if one of those might fit your needs.

share|improve this answer
I wouldn't say that it's a bad idea, I would say that it's more challenging than hosting an email server on a static ip address. – joeqwerty Mar 4 '11 at 15:03
There is still a chance (albeit a small one) that an email bound for your address could be lost without any explanation whatsoever. Running an email server that receives inbound email on a dynamic IP address is like playing Russian roulette with that email, so I stand by my assertion that it's a bad idea. – Brian Showalter Mar 4 '11 at 18:55
just to add on to the "why its a bad idea" thread, if you are sending email from a dynamically allocated IP address, there is a higher chance your email will get trapped by a black-list and may not be delivered. – Peter Carrero Mar 4 '11 at 19:21

It's possible to run a smtp on a dynamic IP with a small delay (due to the caching nature of DNS) on delivery when your IP actually change.

Easiest setup I suppose is dyndns which has clients for all major OS's.

As for the scenario postfix address rewriting should do the trick.

share|improve this answer
There's only a delay if the dynamic ip address changes, which probably doesn't happen very often, and only for those hosts that have the DNS record in their DNS cache, which is not likely unless the OP gets a lot of emails from the same senders. – joeqwerty Mar 4 '11 at 15:04
Agreed, possible delay, but highly unlikely. – Mark Mar 4 '11 at 15:42

For incoming private forwarding it is possible. However, I would suggest looking at fetchmail or some similar mail fetching software. Linux is probably your best choice of O/S for this kind of configuration.

Be aware, that it is possible your email may be forwarded to someone else if your server is down or your IP address changes. DNS caching may cause your IP address change not to be recognized for some period of time after it is updated.

If you wish to send from this configuration relay your outbound messages through your ISPs relay server, or an authenticated connection to GMail using your account. Many server, mine included assume e-mail sent directly from a dynamic IP address is spam. This assumption is well over 99% accurate.

To copy outgoing mail you want to look for automatic BCC (blind carbon copy).

share|improve this answer

You can absolutely run an email server with dynamic DNS. Though you can run an email server on dynamic DNS, there are some hurdles. In regards to previous posts citing the issue with updating your IP from your server, I choose to have my dynamic DNS updated from the firmware within my router. This ensures that regardless of the state of my clients that the IP updating feature is always on (as long as there is not a power outage of course). Even if there was a power outage, the router would eventually get back up and sync to my dynamic DNS host regardless of client activity. With this, your server will need to have a reserved IP address issued from your router so as to not tangle with any other configurations.

As far as the email server aspect, your biggest issue on dynamic DNS will be other email servers marking the mail as spam due to the changing nature and tough identity of a server running on a dynamic DNS. Many email providers, gmail for instance, will mark my emails as spam because it cannot identify the credibility of my server. There are workarounds that I am still trying to hammer out but given the changing IP beyond my router, I will constantly deal with that spam issue.

share|improve this answer

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .