Elk M1EXP invalid MAC address and random IP address after AC failure

T

TriLife

Active Member
Greetings;
 
I am encountering strange behavior on my M1EXP lately. Two issues:
 
1- My area has frequent and long power outages lately. Snow and wind wreak havoc on PG&E at 7,000'. The M1EXP has a separate back up system (along with the router), supplied by a P1215 charger, which monitors low battery.
 
After about 12hrs of no AC, I get a low battery signal and M1EXP shuts off. Unfortunately it never comes back. Running RP2, I have to FIND the M1EXP and it always appears with an odd IP address 192.168.3.64, instead of the 192.168.0.40 static IP it is supposed to be on. In order to bring it back, I have to jumper the board, bring it to the default IP and reprogram from there. Any idea what is going on?
 
2- While troubleshooting this, I ran the M1EXP diagnostic utility. This one tells me that my MAC address is invalid! Any idea how to get it back to a VALID MAC address?
 
Thanks in advance for your help.
 
What MAC address does the M1XEP appear to have, vs what is on the label?
 
You may be running into the same problem that others have seen where the M1XEP loses its factory-set MAC address.  When this happens, people often then see an address of something like 00-40-9D-BA-DB-AD or similar.  Note the BAD in the address.  Other addresses have also been reported.
 
Unfortunately, there is no way to easily change it back to the original setting.
 
Here is a thread where it has been discussed.
 
And here is another thread about the problem.  In post #10, they also wound up with an address of 192.168.3.xxx
 
Hi RAL;
 
Yes, you are right. In my case, the first 7 digits match the label on the board, the last 5 are completely different.
 
In fact, the IP/MAC combo is the same you mention in your post#13 (thread you referenced above).
 
Does this mean I have to get a new M1EXP? or will that one crap out on me as well, the next time there is a low power voltage? Has ELK taken a position on this?
 
I recently came across a post, where someone had cloned the M1EXP with a Raspberry or an Arduino. Do you know more about this? given the low power consumption of either of these boards, it would make sense...
 
Cheers
 
TriLife said:
Hi RAL;
 
Yes, you are right. In my case, the first 7 digits match the label on the board, the last 5 are completely different.
 
In fact, the IP/MAC combo is the same you mention in your post#13 (thread you referenced above).
 
Does this mean I have to get a new M1EXP? or will that one crap out on me as well, the next time there is a low power voltage? Has ELK taken a position on this?
 
I recently came across a post, where someone had cloned the M1EXP with a Raspberry or an Arduino. Do you know more about this? given the low power consumption of either of these boards, it would make sense...
 
Cheers
Click to expand...
 
I don't think you need a new XEP.  And unfortunately, a new one could crap out the same way.  I'm pretty convinced that there is a firmware bug that causes this problem.  Whether or not a power fluctuation can bring it about isn't clear.  It might just be a coincidence. 
 
When the MAC address changes, it appears that the rest of the XEP still functions properly, except that you have to find a way to deal with the changed address.  From the posts that I have seen, it sounds like the new MAC address is stable - i.e. it doesn't continue to change to other values.
 
One way to deal with it would be to enable DHCP and then have your router assign your desired fixed IP address based on the new MAC address.
 
I don't think I saw the post about cloning the XEP using a RPi, but I've thought about what it would take to do that.  It seems like it shouldn't be that difficult, and would be wonderful to have some open source code that could be enhanced beyond what the XEP does today.
 
RAL said:
I don't think you need a new XEP.  And unfortunately, a new one could crap out the same way.  I'm pretty convinced that there is a firmware bug that causes this problem.  Whether or not a power fluctuation can bring it about isn't clear.  It might just be a coincidence. 
 
When the MAC address changes, it appears that the rest of the XEP still functions properly, except that you have to find a way to deal with the changed address.  From the posts that I have seen, it sounds like the new MAC address is stable - i.e. it doesn't continue to change to other values.
 
One way to deal with it would be to enable DHCP and then have your router assign your desired fixed IP address based on the new MAC address.
 
I don't think I saw the post about cloning the XEP using a RPi, but I've thought about what it would take to do that.  It seems like it shouldn't be that difficult, and would be wonderful to have some open source code that could be enhanced beyond what the XEP does today.
Click to expand...
 
Hi RAL;
 
Thanks for the reassurance that a new M1EXP won't help. Indeed, the unit seems to be working fine with the new MAC address.
 
Both times that the problem occurred, it was when the unit was on the battery back-up until it shut down, so I'm thinking the cutoff voltage of the P1215 might be too low and the M1EXP is behaving erratically. I now switched the backup to the main board backup, powering it from VAUX of the M1G. Testing right now. Will let you know.
 
The suggestion with using an assigned DHCP address is a good one and I already tried it. Unfortunately, my router also recognizes the MAC address as INVALID and refuses to reserve an IP address.
 
I am toying with the idea of changing my whole network to x.x.3.x and assigning the M1EXP's static IP to x.x.3.64. That way the erroneous IP and the assigned IP are the same. What I don't know is whether any other settings in the M1EXP change. I have always sent the RP2 data to the M1EXP after this problem occurred, overwriting whatever was in there after the power failure and IP reassignment. Unfortunately, I don't have time to test this idea on this trip...
 
I did shoot a mail to techsupport@elk. Let's see what they have to say. I hope it is something else than " sorry you are not a registered tech"...
 
The system is now on backup batteries, drawing 300mA on an 18AH battery. Been working fine for the last 7 hours. Will let you know how this turns out.
 
 
Here is the GitHub post about the RPi emulator: https://github.com/billchurch/node-elkether
 
 
Cheers;
 
TriLife said:
Hi RAL;
 
Thanks for the reassurance that a new M1EXP won't help. Indeed, the unit seems to be working fine with the new MAC address.
 
Both times that the problem occurred, it was when the unit was on the battery back-up until it shut down, so I'm thinking the cutoff voltage of the P1215 might be too low and the M1EXP is behaving erratically. I now switched the backup to the main board backup, powering it from VAUX of the M1G. Testing right now. Will let you know.
 
The suggestion with using an assigned DHCP address is a good one and I already tried it. Unfortunately, my router also recognizes the MAC address as INVALID and refuses to reserve an IP address.
 
I am toying with the idea of changing my whole network to x.x.3.x and assigning the M1EXP's static IP to x.x.3.64. That way the erroneous IP and the assigned IP are the same. What I don't know is whether any other settings in the M1EXP change. I have always sent the RP2 data to the M1EXP after this problem occurred, overwriting whatever was in there after the power failure and IP reassignment. Unfortunately, I don't have time to test this idea on this trip...
 
I did shoot a mail to techsupport@elk. Let's see what they have to say. I hope it is something else than " sorry you are not a registered tech"...
 
The system is now on backup batteries, drawing 300mA on an 18AH battery. Been working fine for the last 7 hours. Will let you know how this turns out.
 
 
Here is the GitHub post about the RPi emulator: https://github.com/billchurch/node-elkether
 
 
Cheers;
Click to expand...
 
Thanks for the link to the GitHub project.
 
It will be interesting if you can cause the problem as the battery runs down.  It's certainly possible that the processor behaves erratically if the voltage gets too low.  But the flash memory location that holds the address is supposed to be protected by a lock word, so it would seem that it would take a sequence of errors to change it.  I suppose that the low voltage might prevent the lock work from working, and then an errant write to memory could corrupt it.  But I wouldn't expect that the same bad address would result on multiple systems.  So that leaves me thinking it is really a bug that causes it. 
 
If you get a response from Elk, please share it here!
 
I believe the BADBAD MAC issue is addressed in the latest XEP FW or at least partially as a spar.
 
Invalid Default of Static IP Address - Fixed an issue that could cause the static IP Address to change to an invalid address of 192.168.3.64 during a reboot or power restart. In some cases the MAC address might also change to 00409D:433597 or 00409D:BADBAD. To restore the correct MAC address the M1XEP would have to be returned to Elk’s factory. This update resolves both issues. Upon bootup or power restart the M1XEP should now restore to the last known Static IP address the technician programmed and stored in the flash memory. Should the flash memory ever become corrupted the M1XEP will revert to the Elk default Static IP address which is: 192.168.0.251.
 
I've gotten away from DHCP for the XEP on installs. Creates more issues over time. Set it as a static, pull the DHCP address from the pool and move on, unless you're MAC filtering.
 
DELInstallations said:
I believe the BADBAD MAC issue is addressed in the latest XEP FW or at least partially as a spar.
 
Invalid Default of Static IP Address - Fixed an issue that could cause the static IP Address to change to an invalid address of 192.168.3.64 during a reboot or power restart. In some cases the MAC address might also change to 00409D:433597 or 00409D:BADBAD. To restore the correct MAC address the M1XEP would have to be returned to Elk’s factory. This update resolves both issues. Upon bootup or power restart the M1XEP should now restore to the last known Static IP address the technician programmed and stored in the flash memory. Should the flash memory ever become corrupted the M1XEP will revert to the Elk default Static IP address which is: 192.168.0.251.
 
I've gotten away from DHCP for the XEP on installs. Creates more issues over time. Set it as a static, pull the DHCP address from the pool and move on, unless you're MAC filtering.
Click to expand...
 
Thanks DELInstallations. I just did the FW upgrade to 2.042. I'll live with the alternate MAC address, since requires a return to factory.
 
In the meantime, I did some mods to the system, which also eliminated the problem: I had all peripherals on a separate Battery Backup and the Mainboard on it's own. I moved the M1EXP to VAUX and ran a test. with 18Ah, I get in excess of 30hrs autonomy and the cutoff voltage seems to be higher, since the IP doesn't go rogue.
 
In the past, I used to get occasional hang ups of the M1EXP and my router (usually due to brownouts). Aaron, the programmer, who wrote the M1 Touch Pro provided a trick, which has worked well for me: Through an IOboard relay and a Rule, I recycle the power to the M1EXP and the Router every 24hrs. Problems haven't returned since.
 
Thank you All for your help.
 
BTW, Elk Still hasn't responded to my mail. Why am I not surprised?!
 
Cheers;
 
I just had my RP2 Mac address change to 00409D:433597 and IP Address of 192.168.3.64. I did not see the resolution to this problem in this thread. Can someone share the solution?
 
The cause of the change in MAC address is a bug in the firmware.  This was supposedly fixed in v2.0.42.  There's no way to change the MAC address back to the original value without returning the XEP to the factory.  Best thing to do at this point is live with the new MAC address.
 
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