Networking Problem With HM4


 
Yes to all. I have also set the wireless with a static ip and still no joy. HM is showing at 'interfaces' that the wireless is connected and is up. I think it is time to call it a night and start fresh in the morning. Thanks
 
I'm wondering if you ever worked this out? When I first setup my WiFi for some reason I was able to access the HM page from a computer that was wired to my router (HM had WiFi connection with no cat5 cable connected) but NOT from other wireless computers/devices. For some reason wireless devices were being blocked from communicating directly with each other. It was a strange problem, seemed like a router problem so I poked around with the settings until I got frustrated.

The router was a LinkSys WRT54G (not running LinkMeter, just used as a WiFi router), the firmware was very old so I updated the firmware, still no joy. So I decided to load the Tomato (open source) firmware on my router, still no joy. I noticed some settings looked really strange after I installed Tomato so I did a factory reset to default values and everything came to life and has worked perfectly since. I suspect that there was some screwed up setting in the router and doing a factory reset would have fixed the problem running any firmware.

At any rate, I thought I would throw that out to you hoping it might be helpful...
 
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Hey Ralph,
Still no joy. What is bothering me is that I was able to access the HM a few weeks ago before I have a problem with my display. I am beginning to wonder if the edimax is bad. Bryan mentioned an alternate a few days ago and I believe it is available locally. I will probably run over and pick one up. When I was able to access via the edimax, I did not have internet access. Your solution will probably solve that. I know one thing though, my case will arrive this week and I need to be ready for a cook friday night. I am going to hardwire a cable to the patio for Cat5. That will give me what I need. Very frustrating. Also in the next week or so I am installing a new access point system that I am testing before installing for my clients.
 
You could plug the edimax into a different computer to test it if you've got one around....
What are you using for a WiFi router? If you have you HM online via lan cable I could look at the config for you to see if I can spot an issue if you like...
 
Already tried that. Just ordered a new edimax from Amazon, it will arrive tomorrow. I am also tempted to build a second hm4 to test with. Already have most of the parts. Just need a circuit board, rpi, and a few other small parts. Will probably order those in a few days. Once I have the edimax will test further. Still going to setup wired ethernet for patio. that way I am covered no matter what. Bob
 
That is correct. I am going to check it again to make sure, but so far joy. I think I will check it on a laptop now.
 
Ok, the edimax works fine on a laptop if I install the drivers from the included disk. I tried what seemed to previously work but does not now. I tried Bryan's setup as detailed on a link at the beginning of this thread. All that works is hardwire network. I am at my whits ends about this. I will run the previously mentioned network cable to the back porch as a stopgap measure. I am also ordering the few parts I need for a new build. Something is screwy here and I can only assume it is something I did or my infrastructure for my wireless network. That will be redone for other reasons in the next few weeks as soon as parts are available. I WILL figure this out no mater what it takes.
 
What's the overall goal with your network setup, to have both wired and wifi working at the same time?

I've read the 1000+ page canonical guide on how TCP/IP works so I'm not a networking neophyte and I didn't even try to attempt that. If you just want wifi working, wipe the card and add the "norestore" option to the command line. Once it is done booting for the first time, a minute or so later, plug a keyboard in and type "wifi-client yourssidname yourpassword" and reboot.
 
I use this, http://www.roadkil.net/program.php/P14/Disk Wipe, to "unformat" my SD cards

There is also no technical reason, from a TCP/IP perspective, that the wired and wireless interfaces can't be on the same subnet as long as the web server is configured to listen on both interfaces. Now this does not mean that there not is something about OpenWrt that is causing an issue.
 
Rob Trainer said:
I use this, http://www.roadkil.net/program.php/P14/Disk Wipe, to "unformat" my SD cards

There is also no technical reason, from a TCP/IP perspective, that the wired and wireless interfaces can't be on the same subnet as long as the web server is configured to listen on both interfaces. Now this does not mean that there not is something about OpenWrt that is causing an issue.
Click to expand...

I agree and believe the above statement to be completely accurate. IMHO you probably have semething wrong in your network settings, the reason I say this is when you posted your initial info you had some strange stuff going on there (when you didnt have internet access even via the working lan cable). Either that or you do indeed have an issue with your wireless network itself.

Like I asked before, what kind of wireless router are you using? That would be a good starting point, perhaps check the firmware on the router, update it, do a FACTORY RESET on the router settings and set it up fresh. OR if you can port forward port 80 and port 443 to the IP of the wired lan on your HM and share the info with me I would be glad to log in and take a look at your network setup on your HM. You can just set a basic password for the time being like 1234 and then change it after I'm done if you are worried about that, and send the IP via private message if you dont want it posted in the forum (understandable) At any rate, that is my offer to help.

Otherwise you can keep poking at it from every direction. Rob suggested you UNformat the card (his method would delete the hidden partitions I assume). you cant see them on a windows machine but can on linux, they contain a backup of your settings and will keep trying to plug them in if you dont stop it. As Bryan suggested, on the newest release you can add the "norestore" option to the command line to make it not restore your settings upon boot.

If your wired lan is working, your edimax is blinking, and your wifi router shows the edimax connected then there has got to be some settings that are screwed up, either in the HM or in the wifi router.
 
Rob Trainer said:
There is also no technical reason, from a TCP/IP perspective, that the wired and wireless interfaces can't be on the same subnet as long as the web server is configured to listen on both interfaces.
Click to expand...
From a TCP/IP perspective they can be on the same subnet but TCP/IP basics says "When I want to route this packet, I look at the routing table, find the most exact match with the lowest metric, send it out that interface." If the interface flag or RUNNING or not RUNNING (cable plugged in) makes no difference because that's not TCP/IP's job.

Why this works on most modern systems is that another userland application watches the adapter state and when it goes down removes that route from the routing table. Take for example the nas machine we have at work:
Code: 
eth0      Link encap:Ethernet  HWaddr 00:11:23:B1:44:4F
          inet addr:192.168.100.156  Bcast:192.168.100.255  Mask:255.255.255.0
          UP BROADCAST NOTRAILERS RUNNING MULTICAST  MTU:9000  Metric:1
          RX bytes:1764854439294 (1.6 TiB)  TX bytes:67876811067 (63.2 GiB)

eth1      Link encap:Ethernet  HWaddr 00:11:23:B1:44:50
          inet addr:192.168.100.146  Bcast:192.168.100.255  Mask:255.255.255.0
          UP BROADCAST NOTRAILERS RUNNING MULTICAST  MTU:9000  Metric:1
          RX bytes:179345230124 (167.0 GiB)  TX bytes:415799431 (396.5 MiB)
Golly both on the same subnet how can that possibly be! Well if you ping either IP address you actually get a response from eth0 because that's what's in the routing table:
Code: 
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         192.168.100.254 0.0.0.0         UG    0      0        0 eth0
192.168.100.0   0.0.0.0         255.255.255.0   U     0      0        0 eth0
192.168.100.0   0.0.0.0         255.255.255.0   U     0      0        0 eth1
If I unplug eth0, ifconfig shows it still has an address, just without the running flag
Code: 
eth0      Link encap:Ethernet  HWaddr 00:11:23:B1:44:4F
          inet addr:192.168.100.156  Bcast:192.168.100.255  Mask:255.255.255.0
          UP BROADCAST NOTRAILERS MULTICAST  MTU:9000  Metric:1
But wonder of wonders I can still ping it because the routing table has been fixed
Code: 
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         192.168.100.254 0.0.0.0         UG    0      0        0 eth1
192.168.100.0   0.0.0.0         255.255.255.0   U     0      0        0 eth1
This doesn't happen on OpenWrt because whatever application is removing the route isn't there.

I figured out this morning that both lan and wifi can be on the same subnet, but both must be configured for DHCP. This works because if the cable isn't plugged in, the adapter never gets an address and never gets into the routing table.
 
Well, I've got the wired lan set with static IP 192.168.1.98 and the WiFi set with static IP 192.168.1.99 and they both seem to work all the time. I've tried booting with both wired and wireless lan connected at the same time, the HM web loads from both IP's, and I've tried with just wired and just wireless which works fine also. I've not found a scenario where it doesn't work actually (with my config set for static IP's on both).
Like I said before, this is not a problem generally with networking, on windows machines you can run multiple network devices with static IP's or even multiple static IP's on one device without any problem, not sure if/why linux or openWRT would have an issue with it, from my experiments (at least on my system) it doesn't....
 
I know I keep asking this, but it boggles my mind how that works! Can you ssh into your device and copy-paste the output of `route`, then do the same with it still running after you unplug the ethernet?
 
I've got it out on the deck now away from the lan wires, but I will be glad to do that when I bring it in and have both connected. Right now this is what it shows me without the lan cable connected....

Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
default 192.168.1.250 0.0.0.0 UG 0 0 0 wlan0
192.168.1.0 * 255.255.255.0 U 0 0 0 eth0
192.168.1.0 * 255.255.255.0 U 0 0 0 wlan0
 
OK, I pulled the HM in cause my Kamado doesn't really need it for short cooks anyway...

I have Static IP assigned to both wired LAN and WiFi on the rPi.

LAN: 192.168.1.98
WiFi: 192.168.1.99

I connected the rPi to my LAN cable, booted and waited 5 minutes to make sure everything was loaded and connected. Then used a computer with a wired LAN connection to my WiFi router to call the rPi wireless IP (192.168.1.99), connected and logged in fine. Then I called the rPi wired LAN IP (192.168.1.98), connected and logged in fine. Tried them both one more time separately to be sure, both working. So good so far...

This is what I see when I connect with PuTTY and enter the 'route' command:

Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
default 192.168.1.250 0.0.0.0 UG 0 0 0 wlan0
192.168.1.0 * 255.255.255.0 U 0 0 0 eth0
192.168.1.0 * 255.255.255.0 U 0 0 0 wlan0

Now I unplug the LAN cable, for the first time I find a scenario where I can not load the HM page (using the same computer in above), however, the HM page loads right up from my other computers on the network. Very odd. PuTTY also still connects fine from the other computers on the network but not the original computer with the wired lan connection to the wifi router. When I enter the 'route' command I see this (same):

Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
default 192.168.1.250 0.0.0.0 UG 0 0 0 wlan0
192.168.1.0 * 255.255.255.0 U 0 0 0 eth0
192.168.1.0 * 255.255.255.0 U 0 0 0 wlan0

Being a little stymied here I tried rebooting the original pc with the wired lan connection, still no reply from the HM webpage at the wireless IP. It then came to me that the computers which still load the HM page are connecting to the HM via port forwarding in the router (calling out to the router IP), so I tried the router IP on the machine that has been failing to connect and guess what, the HM page loaded.... PuTTY too....

So it's an odd situation, the only scenario where it fails to connect for me is if I boot the rPi with wired AND wireless lan connections, then disconnect the wired connection, at that point the wireless does not respond to it's IP directly (until it reboots), however, it still responds to port forwarded requests from the router....

...and with a big spin of the karmic wheel, as I am performing this experiment the song "can't explain" by the WHO came over my radio, no fooling....
 
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Wow that is extremely interesting, thank you for all that information. That's very strange that the router can get to it but you can't access it from the local ip directly. I'm going to set that up myself and see if I can get like results.

I've also done some experimentation by adding routing metrics to the interfaces without luck, but I also tried adding multiple IPs to the ethernet adapter. Leaving both the static IP and setting it to DHCP on the wired interface gave me access to it both by changing my machine's IP to that static subnet but also allowing access from my network. If I unplug the cable it stops working, but if I reboot the wifi works fine (also the wired if I plug it back in but it is actually going through wifi at that point).So it seems stable either way as long as you assume that you have to reboot between inserting/removing the ethernet cable. I think that's going to be the default configuration in future releases.

EDIT: But I am going to continue experimenting because network configuration really does need to be easier.
 
Brian...Why do you think this should not work? When the browser makes a connection to an interface, that connection is open until the web server returns data. The web server will always return the data using the same interface from which the request originated regardless of the routing (because the connection never closed). So as long as the web server is listening on both interfaces it should respond to requests on both.
 
Rob Trainer said:
The web server will always return the data using the same interface from which the request originated regardless of the routing (because the connection never closed)
Click to expand...
Connection closed or not, sending a packet back doesn't go through a virtual pipe that goes back through the path the incoming packet took. Both incoming and outgoing packets are separate things, the receiver doesn't know how it got there. If you want to send a IP packet to X it will follow the rules of IP-based routing, which is to select the lowest metric route from the routing table with the most specific netmask that matches the target IP.

In fact, when the website doesn't come up when your cable is unplugged, your request is actually getting to the web server but the connect never fully opens. The ARP from the client machine has succeeded. The SYN packet goes out and is received by the rPi, but no SYN/ACK makes it back to the client.

You can set up routing rules that essentially makes it so packets go back on the same interface they came from, but that requires creating a separate routing table per interface called "Split Access".

And having multiple interfaces in windows is a completely different beast as it has a service that dynamically updates the routing table based on link state as well as link bandwidth.
 
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