Richard, The safest way to do this is to enable and configure SMTP AUTH. This is based on SASL, and you'll need to yum list "*cyrus-sasl*" to see the packages you need. You can use plain text auth over starttls and the user can then authenticate with their username and password securely. If you don't use starttls, you'll need a more secure authorization mechanism. This will allow the user to authenticate and relay mail no matter what IP address or network they are accessing your server from. Here's a link for more information. http://www.sendmail.org/~ca/email/auth.html Lonnie On 09/11/2010 10:58 PM, Richard Gliebe wrote: > We have to setup relaying for a person, which is connected to the > internet with a dailup connection. So every x days the IP and the > hostname will change. > > Is there a solution how to set up /etc/mail/access to relay there Emails > permanent (maybe: FQDN from the 'mail from' domain, which is permantly - > <ourdomain>.at?) > > Configure our access file with wildcards (IP: xxx.xxx.) is to insecure > for us. > > At the moment, after there IP was changed, I also have to change the > access file. > > Or is there another way to fix my problem. > > pop3 before smtp (our client fetches there emails with POP3s) isn't an > option for us. > > many, many thanks > Richard > -- Lonnie Maynard, Vice President of Engineering, Aspen Systems, Inc. lonniem at aspsys.com http://www.aspsys.com 3900 Youngfield Street Tel: +01 303.431.4606 ext:135 Wheat Ridge CO 80033, USA Fax: +01 303 431 7196 Toll Free: 1 (800)-992-9242 ext:135