title: Why is my peripheral device not connected to others?
body: <p>My iPad mini(iOS7.1.2) has my app using CoreBluetooth to act as a peripheral device. Its state(<code>CBPeripheralManager::state</code>) is <code>PoweredOn</code>, and there're no any other errors when adding and starting advertising my service. However, <strong>any central devices around the peripheral cannot connect to it.</strong> </p>
  
  <p>I, of course, thought there might be problems about the central devices. It was not true because those central devices could connect with other peripheral devices except "that peripheral device". When I tried to connect with the peripheral device, <code>- (void)centralManager:(CBCentralManager *)central didDisconnectPeripheral:(CBPeripheral *)peripheral error:(NSError *)error</code> was called. (with error code 7).</p>
  
  <p>Peripheral doesn't show any error, and centrals cannot connect till rebooting the peripheral device. What should I do more? Should I upgrade the device to iOS8?</p>
  
  <p>p.s. The central devices are various, from iPhon4s to iPhone6+, and from iOS7.0.6 to iOS8.2. No problems with central devices, and peripheral devices except it.</p>
  
  <p>p.s. It was occured just once, but when in strange state, the peripheral state was suddenly changed to <code>Resetting</code>, and <code>PoweredOn</code> again. After that, there are no problems about connecting. I don't know why the state was suddenly changed to  <code>Resetting</code>, and how the state was changed.</p>
  
  <p>+added @ 04081228 (GMT+0000)</p>
  
  <p>I found some fishy logs from the central device which is trying to connect with the peripheral device. These below are some of the logs.</p>
  
  <blockquote>
    <p>Apr  8 21:20:57 BTServer[61] : ATT        Failed to locate GATT primary >service on device "9C3C82F8-50F5-FE2C-EE41-D8B8B85D7DA3"</p>
    
    <p>Apr  8 21:20:57 BTServer[61] : ATT        Aborting command as device >"9C3C82F8-50F5-FE2C-EE41-D8B8B85D7DA3" is no longer connected</p>
    
    <p>Apr  8 21:21:08 BTServer[61] : ATT        Failed to locate GATT primary >service on device "9C3C82F8-50F5-FE2C-EE41-D8B8B85D7DA3"</p>
    
    <p>Apr  8 21:21:08 BTServer[61] : ATT        Aborting command as device >"9C3C82F8-50F5-FE2C-EE41-D8B8B85D7DA3" is no longer connected</p>
  </blockquote>
  
  <p>I found <a href="http://goo.gl/Mp7PJJ" rel="nofollow">the comment from github</a> that this is known issue of iOS. I couldn't find any other information about this, though.</p>
  
  <p>+added @ 04081304 (GMT+0000)</p>
  
  <p>I also found this log. I'm not sure what this means, neither.</p>
  
  <blockquote>
    <p>Apr  8 22:02:03 BTServer[61] : ATT        Failed to set MTU to 158 with result BM3 STATUS 14</p>
    
    <p>Apr  8 22:02:13 BTServer[61] : ATT        Failed to set MTU to 158 with result BM3 STATUS 14</p>
  </blockquote>