Setting up DHCP and NAT on apple extreme with Virgin Media SH (APPLE)

3

I'm currently going mad trying to get my Apple Time Machine to be the DHCP and NAT Server. I've turned off DHCP in the Super Hub config and turned DHCP and NAT on in the Time Machine. Doing this, I thought, would be all that I'd need to do but it's not able to reach the internet.

There's an option to turn the Super Hub into Modem mode but I'd like to keep the WiFi options on it as it's down stairs and the Time Machine upstairs. The WiFi on the Super Hub is a hell of a lot better than the Time Machine's as well.

Am I already trying to do something I can't?


Steps Taken

  1. I turned off DHCP in the Super Hub.
  2. I turned on DHCP in the Time Machine - 10.0.1.100 - 10.0.1.200
  3. I assigned a static IP to the Super Hub - 10.0.1.2
  4. I went to the internet tab in airport utility and assigned IPv4 - 10.0.1.99, and assigned router IP to 10.0.1.1, BUT no matter what values these were in the 10.0.1.### range the utility would say the WAN IP conflicted with my DHCP range.
  5. After much messing about I tried my external IP for the IPv4 field and tried a 10.0.1.### for the router. Same error again. Then decided to give both router and IPv4 the same external IP and that allowed me to update the routers config, but still no internet.

The Angry Saxon

Posted 2015-04-30T07:05:23.347

Reputation: 168

[I think you mean server not client, btw in your opening para] - Unless you dumb down the 'super' [misnomer if ever I heard one] hub to modem mode, you will be fighting double NAT. Those things work best when they're dumb, then put a decent router behind it. Survive without the built-in wifi, you can get a decent AP for a few quid. Alternatively, you'd need to set the Airport up in Bridge mode & let the Virgin box do DHCP/NAT – Tetsujin – 2015-04-30T07:53:41.150

I really want to get the Time Machine doing the DHCP and NAT as I'm in the process of setting up a OS X server. OS X server will auto-magically open / close ports required for the services if the Time Machine is looking after NAT. Something I can do myself anyway but if the functionality is there I'd like to make use of it. I'm sure 3 months down the line I'll have it back to how it was due to it doing my head in ;) – The Angry Saxon – 2015-04-30T13:06:56.093

Sounds like a good solution - but I'm still convinced dumbing the virgin box down to modem will ultimately make the whole job easier. I have a similar rig here, though I've a Sophos UTM behind mine, rather than an Airport. Wifi is done on separate APs, wired one on each floor. Re: 'doing your head in' I think that's what the Superhubs are designed to do, to all but basic users ;-) – Tetsujin – 2015-04-30T13:13:47.330

BTW, the super hub's IP changes depending on whether it's routing or just dumb modem. In modem mode, it's 192.168.100.1 in Router mode it's 192.168.0.1 – Tetsujin – 2015-04-30T13:16:21.180

Right okay. So I dumb'd down the Super Hub and turned it to modem mode, but now I've hit another stumbling block. I've got a Netgear switch between the, now modem, and the Time Machine I wanted to use as DHCP and NAT. Would this cause issues? I've been at this all day and I'm slowly loosing the will to live. What I'm guessing the issue is now is the modem goes to the router, which is sent all over the house, rather than direct to Time Machine and then to router. Or would that not matter? – The Angry Saxon – 2015-04-30T17:33:02.730

would be better as Modem - Airport - switch - rest of house. Where did this extra router spring from? – Tetsujin – 2015-04-30T17:36:55.263

1So sorry my mind isn't working properly. It's not a router it's a switch. I'll give that a go. By turning the SH into a Modem I loose 4 ports on the back that things like the TiVo and PS4 are using. So needed to give them something. I might be okay though by just swapping round the Time Machine and switch though. I'll give that a go now. – The Angry Saxon – 2015-04-30T17:43:15.183

Wish me luck! ;) – The Angry Saxon – 2015-04-30T17:43:47.930

Yeah that's done it. Shame that it's had to be done that way, but f**k it, it's working :D – The Angry Saxon – 2015-04-30T18:13:01.750

Best, long-term. You now are rid of the infernal Virgin box & have a decent, operable system behind it ;-) I never looked back after I set up the Sophos, maybe 3 years ago now. Prior to that I had a Windows server doing the same job. Don't think I've used an ISP router as they intended in over 15 years ;-) – Tetsujin – 2015-04-30T18:14:54.360

Thanks man for talking me through it. If you want to submit an answer outlining what I've done I'll be happy to accept it. – The Angry Saxon – 2015-04-30T18:16:40.213

OK, will do - I might have think about it overnight & do something in the morning - someone handed me a beer… well, 3 now… not best for coherent structuring ;-) – Tetsujin – 2015-04-30T18:32:14.937

Very nice. Sounds like plan actually. Enjoy – The Angry Saxon – 2015-04-30T18:32:48.893

Answers

1

Distilled from comments…

The best solution I've ever found for a Virgin SuperHub is to dumb it down to pure Modem mode & set up a decent Router behind it. Saves having to bridge the good router & stops the SuperHub's tiny brain having to think at all.

You will lose the SuperHub's WiFi but I think it's a fair swap to finally be in full control of your routing/firewall. Bear in mind the SuperHub's IP changes as you switch if over from router to modem [from 192.168.100.1 to 192.168.0.1 at defaults] & that if you ever hard reset it, you will find it easiest to set back up again with a single computer plugged straight into it, to set it back to modem mode; saves having to rejig the entire network for the sake of a couple of button presses on its built-in web page.
It goes without saying that you should change the default admin password.

Once set, you will have to lift all internal switching to inside the new router, in your case, the Airport, so you don't have stray devices outside the firewall unless you are intentionally creating a DMZ [which would be another topic]

So… Modem > Router > Switch > rest of building.

You would need to add WiFI Access Points from the Switch to the rest of the building [or use repeaters] if you need to extend the WiFi.

Your Airport is now in charge of all routing, DHCP & NAT.
Bye-bye SuperHub.

Tetsujin

Posted 2015-04-30T07:05:23.347

Reputation: 22 456

1

I think you need to slowdown and take break :-), reset all then start all over again. start with your main machine (TM) set it up and make sure it is working and then set up the next one.

0m3r

Posted 2015-04-30T07:05:23.347

Reputation: 937

The theory is sound though right? – The Angry Saxon – 2015-04-30T07:45:38.113

yap try keeping both router on DHCP before you turned one off. – 0m3r – 2015-04-30T07:52:24.187