Problem with X32 & iPad

[Original Beef]

I have a Behringer X32 rack which I use with my iPad. At the weekend I was working with a hire company and I took my iPad and synced to their X32 with their router. This was ok for a few minutes then the iPad would lose sync with the mixer but stayed connected to the router. Despite this we changed router and cable and the problem was still there. It is then impossible to re-sync until the router has been rebooted. I assumed it was a problem with their X32 as it's never happened to mine. However, I've just connected to my X32 rack and the same thing is happening. Very bizarre!!

I've just used the iPad with my Yamaha LS9 and Behringer Xair 12 and it's fine with both of those. I deleted then reinstalled Xmix and it still does it.

 

Can anyone help please?

 

UPDATE

 

I've just changed the ip address on the x32 from 192.168.0.1 to 192.168.0.100 and it's fixed the problem. My iPad's ip is 192.168.0.2 so maybe it was too close?? I really don't understand ip addresses etc. I think the ip address on my x32 ended .58 or something but having used my iPad on another mixer it ended up .1 so I reset my x32 to match that rather than the other way around.

 

ADMIN please feel free to delete this unless it may be of use to others

[Rob_P]

192.168.0.1 will have been the ip address of the router, so allocating it to the desk would have caused a clash as they fought for the address.

[alistermorton]

IP addresses are like a DMX address - each device on the network needs a unique one. Hence when you had two devices addressed as 192.168.0.1 you had a routing problem and it would be anyone's guess which one get the packets at any given time, if either. Unlike DMX, they won't both hear it - one or the other or (often) neither.

 

Longer explanation ... this explanation is about the most common, IPv4 addressing - the concepts are similar for IPv6.

 

Each device on the network needs a unique address, and this is a 32 bit number These range from 0 to 4294967295 but remembering and working with long decimal numbers like that isn't easy, so you'll often see them written as what is known as a dotted quad, such as 192.168.0.1, or occasionally in hex, either as a 8 digit string such as C0A80001 (which is the same address) or C0:A8:00:01 which breaks it up a bit. In both forms (dotted quad or hex) this is the 4-byte 32 bit address broken down int its individual bytes, then each byte expressed as a decimal or hexadecimal number.

 

If lots of people try to allocate permanent device addresses (called static addressing, since once set it never changes) you can end up with two people allocating the same address to two or more devices, so there's a way that a device can ask for a free address when it starts up. This is called dynamic host configuration protocol, and the device on the network which keeps track of what addresses are free and in use is the DHCP server and is often in the router. The router, by default, usually sets its own address to the lowest available address. However, this can mean that the address of a device changes every time it restarts , so often devices which need to be found are given a static address so that it is known (though there are more elegant ways around this than setting the address statically).

 

You'll have spotted that this only allows 4 billion addresses, not enough for the world, so there are ranges of addresses which are reserved for "private" ranges, in so far as they won't get routed on the public side of a router. This means that the only device on the network which is "seen" publicly is the public facing side of the router. All the (possibly thousands of) "privately" addressed machines on the private side of the router are not "visible". All of their internet traffci is routed through the router, which makes sure that the right data goes to the right address.

 

So if you have a small network you'll typically have a 192.168.x.y address, on a bigger network you might have a 10.x.y.z address. The ranges 10,0,0,0 - 10.255.255.255 172.16.0.0 to 172.31.255,255 and 192.168.0.0 to 192.168.255.255 are the private ranges. All other addresses are public addresses and are assigned to devices which are public facing.

 

I won't get in to subnet masks (although there are plenty of resources on the intertubes if you're interested) but that's it in a nutshell. So if your router was 192.168.0.1 and your X32 was 192.18.0.2 then your ipad with an address of say 192.168.0.183 would have worked fine.

 

EDITS: chucking the speeling, clarity.

[Original Beef]

Thanks for the replies and information. Looking back it was the same ip address as the router. Lesson learned.

[alistermorton]

There's a couple of ways you can make sure the desk always has the same address, and that you don't get a clash. Usuall yhe best method for getting an address is to let the DHCP server allocate it, as tha tensures that no two devices get the same address. The problem is that you don't know from time to time what the server will dole out, and it might give the desk the same address five times in a row, then the sixth something different, which means you'll have to reconfigure any app which expects to connect to a known address.

 

One way round this is to allocate the desk an address statically. If you do this, you'll have to configure the DHCP part of the router to never allocate that address. It's usually straightformward to llocate a range of addresses that the DHCP server will never give out, then you have a few available for the mixer, your lighting desk etc. Then your iPad can ask for a dynamic address when it connects, and you can be sure that a) it won't clash with your mixing desk or any other device, and b) you'll always know the address of the desk.

 

Another way is to reserve an address for the mixing desk, and set the desk to get it's address by DHCP. This requires you to know the MAC address of the desk, which is slightly more involved than just reserving a range that the server will never give out. You configure the server to only ever give a specific IP to a DHCP request from a device with the specific MAC address. This ensures that a) the mixing desk always gets the same IP and b) no other device can get it.