After Power Fail OS booted to Wireless with Ethenet connected

[DaveC]

After a recent power fail, OS came back connected via the Wireless port rather than the Ethernet port that it normally uses.

I rebooted it using a browser connection and it comes back connected on the Ethernet port.
In the past I have restarted it manually by turning off its power and in that case it also came back connected on the Ethernet port.

In the recent power fail case, one thing that is different than a simple OS power restart or the reboot is that the network infrastructure would not have been back up when OS finished booting.

Has anyone else seen this behavior?

HW: OS 3.2 DC
FW: 2.1.9(3)

Thanks,
Dave

[Ray]

One possibility is that after power break, the OpenSprinkler booted much faster than the router. The firmware uses the following logic to check whether it should go into Ethernet mode or WiFi mode: 1) it detects if the Ethernet module exists by sending a command to the Ethernet module and verify the return value; 2) if it exists, it then does DHCP to attempt to obtain a valid IP address — this step has a 60 seconds time out, if it isn’t able to get valid DHCP within 60 seconds, it goes into WiFi mode. So this could explain why it went into WiFi.

A work-around is to set a static IP on your OpenSprinkler — when using static IP, it will bypass DHCP so as long as it passes step 1, it will stay in wired Ethernet mode. However, setting a static IP on the controller has its own risks: it might result in a IP conflict if your router ends up assigning the same IP to another device. You can avoid that by changing your router’s DHCP configuration to limit the range of DHCP IPs, and give your OpenSprinkler an IP outside of that range.

On the other hand, if this is a one-off issue and you do not anticipate the power break to happen often, perhaps just leave it as is.

[DaveC]

Ray, Thanks for the detailed info about how OS deals with the 2 network ports. Looking at my router’s boot log, the boot from the power fail, where the WAN had to come up too, took longer than 60s. I’ll switch to static addressing for now. I’m not concerned about managing a static address for OS. That said, I really like the network management niceties that come from using DHCP reservations and I may look at a local workaround:

My OS connects to an automation system which will let me know if the network connection to OS is down. Now that I understand how OS deals with the 2 network ports, I could add the ability for the automation system to understand that behavior. E.g. If the Ethernet address fails after some time period, try the wireless address. If successful, reboot OS to try to get back to the wired port (without looping, of course).

Thanks again,
Dave

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