Nodes offline when enabling serial access to gateway

Hi all:

I manage a 30 xbee node network with a X2 coordinator with gateway radio serial access enabled. In this mode I forward AT commands from a remote computer to the network, and AT responses are processes by the same computer. All works fine and I’m able to both polling sensor digital and analog inputs, send/receive data using xbee RS232-RS485 serial adapters and even managing samples sent asynchronously from sleeping devices.

The problem comes when some nodes become offline for a long time. When this happens I have two solutions:

  • Forwarding to the network a “Node Discovery” AT command. This works the most of times and the offline nodes become online.
  • For those times that the first solution doesn’t work, I have to reboot the coordinator disabling the serial access. Then I can see the previously offline nodes in the xbee devices list. Once these nodes are online, I restart again the coordinator enabling the serial access and all works fine for days. Note that I don’t need to run a node discovery when proceeding in this way.

This fact makes me wonder if, when the coordinator is working with the serial access enabled, it performs all the network coordination tasks that it does when working with serial access disabled. In fact, if I only reboot the coordinator when nodes are offline, without disabling the serial access, nodes keep offline thus the only way to recover them is rebooting with serial access disabled.

Any help about this matter will be really appreciated since this network must be working 24x7 and, due to the described problem, now it needs continuous regular management in order to keep all nodes online.

This is the data of the coordinator (retrieved from “System information”):

Model: ConnectPort X2D
Ethernet MAC Address: 00:40:9D:55:12:4F
Firmware Version: (Version 82002549_C1 10/04/2011)
Boot Version: 1.1.3 (release_82002547_A)
POST Version: 1.1.3 (release_82002548_A)
Product VPD Version: release_82002550_A
Product ID: 0x00B2
Hardware Strapping: 0x0775

Same problem today: Two nodes offline, unable to get them online even sending Node Discovery AT commands to the coordinator (something that, sometimes, works at this situation). I reboot the coordinator disabling the serial access, as fast as I can I enable serial access and reboot again. The two nodes become online.

By the previous test I’m pretty sure that the coordinator performs some operation when booting with serial access enabled that allows all nodes become online. If I just reboot it (without disabling serial access) the problem remains.

Please, any help or the experience of any user working with coordinator in serial access (does it happens only to me?) would be helpful.

I’ve upgraded the coordinator firmware to the last available version:

Firmware Version: (Version 82002549_E 01/03/2013)
Boot Version: 1.1.3 (release_82002547_A)
POST Version: 1.1.3 (release_82002548_B)
Product VPD Version: release_82002550_A
Product ID: 0x00B2
Hardware Strapping: 0x0775

Let’s hope that problems became solved. I’ll report the result.