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Optus, SMTP and port forwarding

A.Scott Pringle

Optus, SMTP and port forwarding
« on: November 06, 2003, 05:14:19 PM »
Optus has recently decided to block outgoing SMTP from an e-smith server that has been running for a number of years.
What is the simplest way to get around this?
I have had a look at a few port forwarding scripts and they didn't work for me.
Any help would be much appreciated.
TIA
Scott

Michiel

Re: Optus, SMTP and port forwarding
« Reply #1 on: November 06, 2003, 06:07:17 PM »
Do you mean outgoing or incoming SMTP? If they block outgoing, this effectively means you can no longer send any e-mail as all mailservers on the internet expect mail on port 25. There is no real way around this short of changing ISP.

If they block incoming SMTP (most ISPs tend to do that nowadays for their low-end subscriptions) you have four options:
1/ Get all mail forwarded to a POP3 mailbox and empty it with multidrop
2/ Use dyndns.org's Relay service to get the mail on a non-standard port.
3/ Change ISP.
4/ Talk to your ISP and/or take a more expensive subscription

Options 1 & 2 have their risks and disadvantages. Option 3 means you also have to change DNS, which can take about a week to work properly. I would therefore recommend to talk to your ISP before trying something else.

Michiel

Charlie Brady

Re: Optus, SMTP and port forwarding
« Reply #2 on: November 06, 2003, 06:20:19 PM »
Michiel wrote:

> Do you mean outgoing or incoming SMTP? If they block
> outgoing, this effectively means you can no longer send any
> e-mail as all mailservers on the internet expect mail on port
> 25.

Chances are they make an exception for outbound to their own SMTP gateway. In that case you need to enter their server in the SMTP Smarthost field of the email config panel. This is recommended in any case for anyone on a residential connection, as more and more remote sites are blocking SMTP connections from "dialup" network addresses.

Charlie

Greg Zartman

Re: Optus, SMTP and port forwarding
« Reply #3 on: November 06, 2003, 06:55:55 PM »
> SMTP gateway. In that case you need to enter their server in
> the SMTP Smarthost field of the email config panel. This is
> recommended in any case for anyone on a residential
> connection, as more and more remote sites are blocking SMTP
> connections from "dialup" network addresses.

Does this bypass outgoing scanning for viruses on SME servicelink machines?

Thanks.

Greg Zartman

Michael Soulier

Re: Optus, SMTP and port forwarding
« Reply #4 on: November 06, 2003, 10:32:04 PM »
Greg Zartman wrote:
>
> Does this bypass outgoing scanning for viruses on SME
> servicelink machines?

No.

Mike

A.Scott Pringle

Re: Optus, SMTP and port forwarding
« Reply #5 on: November 07, 2003, 04:03:08 PM »
Probem solved. I checked the settings in e-smith for the Optus SMTP server and they were as they should be. Then I checked the ISP's SMTP server. Optus had changed the IP address used for the SMTP server. Yet they denied changing anything at all, as usual.
Thanks for the help.