Help with change of ISP * Public IPs with Sonicwall Firewall

Over Clocker · 29 Jun 2011 at 12:29

Hi guys,

We have a Sonicwall TZ180 firewall, and the ISP in for our office has changed.

I've changed all the WAN IP, Gateway and DNS settings on our firewall and the internet is now working fine, however we are not receiving any emails to our internal Exchange server.

Our public IP has changed, however I have not changed our MX record as yet as I am unable to even RDP to our internal server via the new public IP.

Any help would be great! Not sure whether it is a firewall config or the public IP is not working correctly!

Thanks,

Mal

sidethink · 29 Jun 2011 at 12:39

The MX record you need to change is in your public DNS. i.e. at whomever provides your domain name.

You will likely need to login to a portal there and update your MX records and hostnames for anything behind the old public IP addresses. This wont be configured on the Sonicwall or any of your servers.

PistolPete · 29 Jun 2011 at 13:39

sidethink said:
The MX record you need to change is in your public DNS. i.e. at whomever provides your domain name.

You will likely need to login to a portal there and update your MX records and hostnames for anything behind the old public IP addresses. This wont be configured on the Sonicwall or any of your servers.

This, unless you host your own authoritative DNS servers - in which case you need to update the MX record there.
Also, you need to remember to update the A record of the mail server too to if you are trying to access it by FQDN.

derfderfley · 29 Jun 2011 at 19:38

Over Clocker said:
Hi guys,

We have a Sonicwall TZ180 firewall, and the ISP in for our office has changed.

I've changed all the WAN IP, Gateway and DNS settings on our firewall and the internet is now working fine, however we are not receiving any emails to our internal Exchange server.

Our public IP has changed, however I have not changed our MX record as yet as I am unable to even RDP to our internal server via the new public IP.l

You need to get your MX records changed to reflect your new Public IP address.
You will also need to speak to your new ISP and ask them to set up a matching reverse record for your new Public IP address.

Over Clocker said:
Any help would be great! Not sure whether it is a firewall config or the public IP is not working correctly!

RDP not working is probably a Firewall config problem, the rule for external RDP access probably needs changing to match your new Public IP address.