Re: BT Business Hub 3 and Static ip's

paulow1978 · ‎28-11-2012

Hi there!,

I am hoping someone can help me with my BT ADSL service. We have an ADSL line for our failover line and it has caused me no end of issues ever since we got the service installed last year. I have been running networks for about 7 years now so i should be pretty good at this sort of thing but the BT business hub and peer adressing system (not to mention the interface on the hub for management) is really frustrating me.

We have 5 public ip addresses and our Hub is suppowed to pass the 5 public ip's to the Sonicwall firewall which sits behind it. So far, I have tried just about every set up imaginable and still suffering from problems. I set up the bt business hub so that my ip addresses are on the LAN side, the hub picked up the sonicwall device and I put that device in dmz plus mode and set dhcp to assign puublic ip's so that the soncicwall interface would get a public ip. Which it duly does AND I can connect a laptop to the internal interface on the sonicwall and get out on the internet. All Good!. However, the sonicwall also needs to be publicly accessible for things like email, web server hosting etc etc. If I jump on to our other internet line i cannot ping the public ip address that i have allocated to the sonicwall. I have triple checked everything (like the firewall on the hub is tunred off for this NAT allocation etc) and it *looks* like it is configured correctly. I did a packet capture on the sonicwlal and a continuos ping and no packets ever reach the wan port on the sonicwall. Its like my public static ip addresses allow outbound connections but not inbound. Is it possible that the 5 public ip addresses i have been allocated are being blocked by BT?

I dont understand the wierd way BT do their networking. Normally on every other service I have ever used you just get a usable block of "real" static ip addresses and be done with it. None of this your hub has to get a public ip and then using that connection it grants you access to your BT assigned public ip addresses. What? I mean seriously!!!

maybe I am just being dumb (has been known in the last!)

any help would be really appreciated.

thanks,

Paul

paulow1978 · ‎06-12-2012

I got further with this.

Amazingly after finding a post on the internet about a possible internal BT routing issue and the peer addressing system not being set up correctly, i followed the posts advise and upgrade to 13 public ip addresses. Guess what? suddenly I can ping the public ip address and login to my firewall!

well, thats not quite the end of the story....I am still as yet unable to assign multiple static ip addresses to one device (i.e. my sonicwall firewall wan port). I have posted another trhead on that.

I find it unbelievable that BT can offer multiple static ip addresses but not actually be able to allow you to assign them to a firewall behind the BT business hub. This is industry standard in SMB's. I may be wrong and would like to be challenged on this but if indeed this is the case then i will be moving over to another ISP in the near future. If anyone at BT is reading this can you please help?

adrianc · ‎13-12-2012

Hi Paul,

Is the issue that the Sonic wall isn't pingable or that it isn't reachable? By default the Business Hub will block pings - you need to go into the firewall configuration and allow ping traffic through. It will still be reachable though even if pings are being blocked.

Adrian

andyt22 · ‎13-12-2012

@paulow1978 wrote:

I dont understand the wierd way BT do their networking. Normally on every other service I have ever used you just get a usable block of "real" static ip addresses and be done with it. None of this your hub has to get a public ip and then using that connection it grants you access to your BT assigned public ip addresses. What? I mean seriously!!!

Using multiple static IP addresses on the BT Business Hub 3 is a bit of a black art - I've been in networks since 1995 and I too was totally flummoxed when I got my Business Infinity connection with 5 static IP addresses! It's nothing like anything else I've set up or used. Basically, it seems that the static IP addresses are super-netted onto an ordinary dynamic IP address (the sort that non- static IP customers have) and for some strange reason, you need to have the Hub 3's internal DHCP server enabled otherwise the static IP addresses simply won't work.

I've also discovered that there doesn't seem to be a way of assigning multiple static IP addresses to the same physical network interface on a computer - with other broadband connections I'd typically run two DNS servers for different domains on the same NIC on the same host server but on different IP addresses but it seems the Hub 3 will only let you use one of your static IP addresses per MAC address. Actually, you can set these addresses statically on the server itself but the hub will only allow data to pass through to one of them.

Andy