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RyanHenryFlag for United States of America

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Switch to Comcast IP on SonicWall TZ100 OS Enhanced


I am currently trying to switch ISP's from Megapath DSL, to Comcast Business class.  The problem I am having is, when I unplug the SonicWall WAN port, and then plug in the Comcast WAN, and configure the Static IP settings, interent works just fine.  However, are company make it's money off of the 3 websites on the webserver.  For some reason when I make the cut over we are unable to hit the websites by their new External IP addresses.

The thought was that I would be able browse to the websites via new External IP's.  Once that tested out then we could log into Network solutions and change the TTL so that the clients would not notice that the IP address changed and dns would work?

I don't understand what I am doing wrong, and I am not familiar with the SonicWall that much.  

"Firmware Version:	SonicOS Enhanced"

I really need help from you experts on this as I am really getting some grief for not having this working.

If there is a way I can plug the new Comcast Line into the TZ100 and make changes and simply cut over great?  If, not then please let me know where you think my mistake is?  Also, I have never been able to test the cut over for more than 20 minutes.  So not sure if there would be some sort of Cache issue for the websites, or if their is another place that I would change the external IP's besides in the NAT policies, and firewall access rules?  But as I said the internet works fine, and are email is through the internet, but the websites, all 3 won't work?


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Steven Vona
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Are you hosting the websites on your network?

If so you will have to change the DNS for each website (A records) to point to the new IP address comcast gave you.
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The website's are setup on our webserver here, but they are registered with Network solutions.  So the only thing I see in our DNS is internal IP addresses, not external.

We have two website's and one FTP site.

Either way, shouldn't I be able to atleast hit the website via external IP and avoid DNS just to check and make sure it works?

For example   (Comcast external IP for website)

because right now I can type in the current external address and the site comes up.

Thanks and any more help would be greatly appreciated?

Do I have this categorized correctly?  Will the Firewall experts see this question still?
You have to login to network solutions and change the ip for the websites to your new ip range.
In preparation for a changeover you can reduce the ttl as short as possible

Is this all I have to do?  One of the other guys has the login to Network solutions, and so what your saying is that you need to change the External IP there and DNS and it will work?

Because If I connect straight to the comcast modem with my laptop and give it an IP,and type the IP it comes right up.  SO maybe this is the reason why Network solutions needs to be changed.

I hope this works.  I am OOO until Tuesday afternoon, but I will have a 4 hour window that evening  to try all suggestions made by you experts here.
Network solutions controls the ->ip
So if your ip changes that is the first thing to change.
Thank you all very much. I will make this change Tuesday at 8pm cst. I really hope this works because I have no idea what to do if it doesn't
Guys I have another question about this.  What I did was just ad the comcast line as a second WAN line and setup fail over.  I was hoping that when I unplugged the Megapath line then the  LAN and WAN would fail over to the new Comcast WAN.

It didn't, as a matter of fact no one recieved and IP address and my vpn connection between the two companys went down as well.

I am really lost here.  For the record after plugging in the 2nd WAN (comcast) we were able to hit our website via IP address)  But we have no network???
a failover wan can handle outgoing connections very well. However incoming connections like websites hosted internally require much more work because the domain is still pointing to the old ip.
Ok, thanks.  SO shouldn't I just be able to loin to the firewall unplug the megapath wan and plug in the comcast WAN and set the static ips.  Then change the external IP's of the websites and then shouldn't it work?  

I lose vpn to my other company when I did this?  All I am doing is changing from 1 ISP to another so how come it's acting so difficult?
You also have to duplicate your rules from wan1->LAN
For wan2->LAN
For all the ip port forwarding to work.
Were are geting rid of megapath friday.  I just want to keep my lan rules and change the wan IP's to COmcast IP's instead.  Any help?

"We are not trying to have fail over or clustering and sorry for the confusion"

Just need comcast to work!

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Aaron Tomosky
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Thank you very much it worked great!