Whenever my isp changes or adds an ip address to the list of mail
servers I cannot connect to the server. In my rules I have put
'mail.myisp.com' as the smtp server and the pop3 server but
occassionally I still cannot connect to the e-mail server. I believe
that they are adding/changing/round-robin the ip addresses for the
mail servers and the script is only picking up one of these addresses.
Is there a way to get around this problem in ipchains and/or
Is the only solution, to run dig every once and awhile and make sure
that I have all of the latest ip addresses included in the filter,
instead of relying on 'mail.myisp.com' in the script?
How do other firewall systems get around this issue (Zone alarm,NIS