Hello tech gurus... OK, I am not in Zurich anymore, but my problem is not likely a geographical one and maybe someone here has experienced same...

We switched our internet provider to SkyDSL satellite internet recently and now we are having all kinds of issues. Occasionally, things just go down. And when I reboot the modem, it seems like there is a game of "musical chairs" with all of my devices trying to re-establish connectivity.

We have a 1 TB Time Capsule, that has worked flawlessly for a couple of years in CH and Spain. We have 1 Mac Pro and 2 MB Pros, a VOIP phone, wireless printer, AppleTV and a few mobile phones that occasionally connect to the network.

Usually, upon rebooting, one or more devices do not connect, we get messages that another device is already using an IP address, SSL connection errors. Very annoying and there is no real pattern. And it did not happen before with a WiMax provider (which was slow but reliable).

After investigating a bit with Google, I thought I found the solution by switching Time Capsule Connection sharing from Bridge mode (which is off) to Sharing a Public IP Address.

But still no love...

Any suggestions would be happily considered!

Which device is providing the DHCP service (the bit that assigns the devices behind it an IP address)? There are a couple of things that could be going on, but one way to get around the IP collisions is to go onto the device that is assigning the IPs and make the lease for the IPs either very high or permanent/never expire (though I'd suggest starting with a long period first, say a month/30 days). You can also assign them to specific machines/devices if you know the MAC.

I'm not familiar with what kind of kit skyDSL uses, but shifting the DHCP to the time capsule should work, though this adds another layer of complexity that you probably don't need.

Have you tried skyDSL's tech support? Or, as I know that's usually a longshot, maybe check the router and see if there are any firmware updates it needs.

When I had the Time Capsule in Bridge mode, I assume the Tooway (skydsl) modem was handling DHCP. When I switched the TC to the Sharing mode, I assumed it took over DHCP.

But results seem to be the same. My installer thinks it is the Tooway device is faulty, but skydsl tech support is crap and they say that is not the problem.

So I continue to fiddle with it. Will try your suggestions.

I could use MAC addresses, but then what happens if a guest comes onto the network?

fduvall

You have too many active DHCP servers (presumably the skyDSL box and the Time Capsule).

Source...
.

ok - thanks to both of you. The link to the manual should help... I was on the Tooway site and there was very little documentation.

fduvall

You can still leave IPs available for guests since any 10.x and 192.168.x IPs aren't routable and, therefore, you have a large number of IPs to leave open for guests. The apple products, if I remember right, use a 10.x IP range for DHCP.

Also, I'd suggest moving the TC back to bridge/repeater mode as this will help simplify the issue until you get it solved.

What happens when your modem does a swan dive is that, suddenly, it appears to be losing it's proverbial mind, also known as the ARP cache so that all of the devices that think they've got an assigned IP, are now in limbo. Then, when you go and reboot one or more of those devices, voilá, you have one system that's just been given an IP that another system still thinks it has. IP collision.

I'd trust your installer, but put the TC back into bridge config, shut off all your devices which require IPs via DHCP, do a full reset of the modem/router, and then see if you can do any configuration with the DHCP to make the lease stick a bit longer (to be honest, attaching them to the MAC is a PITA and likely unnecessary in a home config, so do that only if forced), and then boot your systems.

I also have had the luck that whenever I had issues like this with DSL modem/routers, it was nearly always a firmware fix. Just keep that in the back of your mind if nothing else works.

Good luck as I know these sorts of things can be pretty aggravating.

Hmmm. Still some issues, as I do not have a SkyBox, but satellite internet. And can't find the information about the Tooway modem that I have. And no documentation in the box. Very strange, as SkyDSL has no real mention of this piece of hardware, but they do have a manual for the SkyBox.

Have switched TC back to Bridge mode, but not sure if that means NO DHCP services are being provided by the TC. And I still need to figure out how to access the Tooway GUI.

I seem to only get a limited number of devices to connect upon a reboot, so as I said upthread, it is like musical chairs and 1-3 devices get shut out from the network.

Piss poor documentation and service by SkyDSL...

fduvall

You can plug in an Ethernet cable from your PC / laptop directly to the TwoWay modem and discover the IP given out, including the mask ( which is useful to determine how many public IPs are to be valid ).

E.G: e.g. 123.123.123.1 255.255.255.252 where the .252 means only 4 will be valid )

Sorry, but don't quite understand how to figure out the number of public IPs if my subnet mask ends in 0.

Thanks,

fduvall

A final octet of 0 will mean you can have 255 devices.

Actually 254 addresses, from .1 to .254.
All-zeroes (.0) and all ones (.255) are reserves as network ID and broadcast address. See http://en.m.wikipedia.org/wiki/Subnetwork

If it's in bridge configuration, it shouldn't be providing any DHCP services since, by definition, a bridge is merely a relay/repeater.

When you're noticing devices getting 'shut out' after a reboot of the Tooway, have those devices been rebooted /after/ the reboot of the Tooway?

The way it works is that the modem/router builds a table of hostname/MAC/IP, aka, the ARP table/cache. The fact that the DHCP service is reallocating IPs that devices on the local network already possess is where the problem lies as an ARP probe should have already established which IPs are already in use. It shouldn't do this but that is what appears to be happening from what you describe and why increasing the lease time on the IPs might help in the short term. You might just ask skyDSL to replace the Tooway and see if that works since it sure beats doing the back and forth with customer support, manuals, etc.

I will take a stab despite not being familiar with Apple stuff.

I think:

a) You have a home service, ie a dynamic public IP address issued by Skydsl
b) The TC can act as a full fledged router
c) The Tooway is merely a modem, not having routing or NAT capabilities - nothing much needs to be done with this device

You might need to, if not done so already, do the following:

a) Connect an Ethernet cable from the Tooway modem LAN port to the TC WAN port. The TC WAN port to be configured as Dynamic IP connection permanent ( or equivalent terms in Apple lingo )
b) Re-configure the TC as a full fledged sole router, set up DHCP to wireless and wired clients

That way, 1 dynamic public address will be NATted through the TC providing private IP addresses ( 192.168.x.x, 172 or 10 series ).

Test, including re-powering all devices.

Hope this makes sense. All the best.

In the event you have performance issues, you might want to ( where possible ) replace the ISP issued DNS servers to eg OpenDNS ( DNS server 1 as 208.67.222.222 and DNS server 2 as 208.67.220.220 ).

This can be specified for the WAN port of the TC ( I think so ) as well as DHCP settings on the TC for all wired and wireless LAN users / devices.

http://en.wikipedia.org/wiki/OpenDNS