I recently purchased an LM1200-100NAS to serve as an LTE failover connection for my homelab and noticed a strange issue while setting up my pfSense-based router to use the LM1200 as a secondary WAN connection. When I initially activated the SIM card on Verizon with the LM1200, I had it directly connected to the Ethernet interface on a PC, and did not see any issues with the link dropping after the LM1200 had fully powered up. However, for some reason, shortly after powering up the LM1200 when connected to the router, it connects to the LTE network (the right-most LED goes from orange to green), then the LAN LED illumminates green, but shortly afterwards, the LAN LED extinguishes, and I see the port link is down on the router. The link stays down for a few seconds, then the process repeats unless I force release then renew the IP address on the router's interface via DHCP. Once I do this, the LM1200 stops dropping the link and the router get's an IP address and is able to route out the LM1200 via IPv4, and I am able to reach the management interface of the LM1200 on 192.168.5.1. This seems to happen every time I power-cycle the LM1200, and requires manual intervention to be able to get a valid IP and pass (IPv4) traffic through the device. I was also able to admin disable the router interface (leaving the link up) and then enabling the router's interface and this also seemed to helped as the link some of the time, but it wasn't consistant. This suggests the issue may be timing related. The LM1200 and my router are also being issued an IPv6 IP address from my wireless carrier (Verizon) as well, but I have thus far been unsuccessful in routing out via IPv6. However, the IPv6 issue is an issue for another thread. Note that I currently have the LM1200 in bridge mode. Firmware version: EC25AFFDR07A09M4G. App version: NTG9X07C_20.04.07.06. Web App version: LM1200-HDATA_03.03.103.189. Has anyone seen anything like this? I see that there is a new firmware release due at the end of the month for the LM1200. Is there a possibility that this will address the issue?

JinTu Thank you for capturing the logs. The initial anaylsis points to the issue to handle Verzion SIM activation and APN dynamic change. The issue seeem only limited to using Verizon network. We are still investigating. I will ask your help again when we have a potential fix on the issue. In our own testing using other carrier network, we couldn't reproduce the issue. Thanks

Hi All, Thanks for your patience on Verizon disconnection issue. We are still working on the fixes right now. Will keep you updated in the coming days. Thanks John

stuyboy wrote: John: Any developments? Does the team think we're close to resolution with Verizon? Or is this still way out in terms of finding the problem? We are at the final stage on debugging the issue. Verizon has been contacted and waiting for their feedback on the network logs for the disconnection issue. Still working on it. Thanks

JohnPeng & Et al. What a troubling issue indeed. Please read below for what I've discovered, if you've been reading this topic for months you'll find it quite interesting. AT&T hotspot SIM works fine using Bridge Mode in my LM1200, no link dropping no lost IP addresses, this we know already. All of my testing was done using a MikroTik hAP ac2 running 7.1.3 software for reference. The Verizon hotspot SIM on our business account in the LM1200 in Bridge Mode receives an IP then drops the ethernet link approximately 26 seconds later and of course loses the IP address, then approximately 23 seconds later the ethernet link is recovered and the cycle repeats. This is the first time I've seen the behavior documented to this level of detail. I decided to leave the hAP ac2 running all night long, utilizing the LM1200 with the Verizon SIM and left no devices connected to the router. Curiously the Verizon LTE connection never dropped while no other devices were connected to the router. Further, the ZeroTier VPN connection stayed stable and I was able to remotely access the hAP ac2 without issue. This behavior was most curious and so began my attempt at a theory of why. I had something to do with devices connected behind the NAT of the hAP ac2. Sure enough when I connected a device to the router the next morning the LM1200's connection began the drop and reconnect behavior described above. What is different when the router connects via the Verizon IP vs though the NAT of the router? Should be nothing, right? A proper NAT translates the device IPs behind it and Verizon shouldn't know any better. How could Verizon know? After digging back into years of IP header theory back in my college days, I had mine (it took a few days) - and it was the TTL value was wrong. I added a rule in the hAP ac2 that adds 1 to the TTL of all IP packets passing though the NAT. After doing that, the Bridge Mode connection became solid. No cycling of the ethernet link, nor IP addresses releasing and renewing. Of course, upon removing the rule adding 1 to the TTL the connection is dysfunctional as described above. After dozens of tests, the behavior is controllable and predicable based upon the TTL change. Ok, so your thinking then the Netgear programmers just need to fix this by adding 1 to the TTL when the LM1200 is in Bridge Mode. Wrong! Just for giggles (does anyone really giggle in these moments?) I decided to really go for it and see what the heck was going on and see if I could determine who's issue it was, now that I'd confirmed what it was. No need to blame Netgear if indeed they were not at fault. It's easy and that's wrong. Since the hAP ac2 has a USB port and supports the Verizon USB730L functioning as a pass though bridge device I decided to do an experiment with the same Verizon SIM used in the testing with the LM1200. Surprisingly both the USB730L and the LM1200 exhibit the same behavior where the connection is unstable with an unmanipulated TTL and adding 1 to the TTL stabilizes the connection. Verizon's network used to work properly without TTL manipulation with the USB730L and the hAP ac2. At some point it stopped working. I thought it was a bug in the hAP ac2s software and said well hopefully they'll fix it someday. It wasn't the hAP ac2s software, something has changed Verizon's network, I'm not sure when it changed it's been a while. This is Verizon's issue, not Netgear's. Unfortunately, I don't know how to get this to the right folks at Verizon. Most people who hear this are going to think it's network gibberish when attempting a support call. I tried to get help from Netgear regarding the device and was promised a call back the next day, the call never came and my Case #: 45696214 was closed in 7 days because I was unresponsive. This is where Netgear is at fault. I'm utterly disappointed in Netgear support, closing the case with no call back is absolutely unacceptable. Hopefully this helps someone. --Mike

The end of August has come and gone with no indication of new firmware being available. JohnPeng are there any revised projections on when the LM1200 firmware update will be released?

LM1200 repeatedly dropping link | NETGEAR Communities

232 Replies

JinTu
Star
Sep 01, 2021
The end of August has come and gone with no indication of new firmware being available.

JohnPeng are there any revised projections on when the LM1200 firmware update will be released?
- JohnPeng
  NETGEAR Expert
  Sep 03, 2021
  The latest LM1200 release has been posted online. If your device's IMEI is ending with 0, 1, 2, 3 and 4, it can be upgraded now.
  
  Please do a factory reset after upgrage and clear browser cache to start over again.
  
  Please let me know if you have any questions or issues.
  
  Thanks
  
  John
  - JinTu
    Star
    Sep 03, 2021
    JohnPeng wrote:
    The latest LM1200 release has been posted online. If your device's IMEI is ending with 0, 1, 2, 3 and 4, it can be upgraded now.
    
    Thanks JohnPeng, my IMEI ends in 7 and I don't see the firmware available to update online, nor can I find it on Netgear's support site. Any projections with other IMEI's will be able to access the firmware update?
- kingtom
  Tutor
  Sep 25, 2021
  JinTu wrote:
  The end of August has come and gone with no indication of new firmware being available.
  
  JohnPeng are there any revised projections on when the LM1200 firmware update will be released?
  Not yet.
ivioo
Initiate
Sep 17, 2021
I just bought this and have the same issue with Verizon also. It connects, passes data then all of the sudden the cell link LED goes from green and flickers red then the LAN led goes out and the LAN connection is gone. Then everything reconnects, it does this cycle over and over. Not sure where to go from here. Can't really trouble shoot when the LAN connection drops. I'm using a Unifi UDM Pro. Seems like if I plug the modem straight into the PC I don't see the issue. Modem says it has the latest FW installed. How do I fix this?
- JinTu
  Star
  Sep 21, 2021
  I did some additional testing with the LM1200 in router mode and it essentially behaved the same (Link drops repeatidly unless DHCP force renewed, and then after the link is up IPv4 passes traffic, yet IPv6 does not)
  
  ivioo wrote:
  I just bought this and have the same issue with Verizon also. It connects, passes data then all of the sudden the cell link LED goes from green and flickers red then the LAN led goes out and the LAN connection is gone. Then everything reconnects, it does this cycle over and over. Not sure where to go from here. Can't really trouble shoot when the LAN connection drops. I'm using a Unifi UDM Pro. Seems like if I plug the modem straight into the PC I don't see the issue. Modem says it has the latest FW installed. How do I fix this?
  Interesting that you are also seeing the same behavior with the link dropping when using Unifi hardware. I hadn't mentioned it in my initial post, but I have my LM1200 connected to a port on a Unifi Pro 24 POE switch (using a POE splitter to power the LM1200). Perhaps there is some inherent issue between the LM1200 and Unifi switchports and the DHCP thing is a red herring?
PeterG5000
Tutor
Sep 22, 2021
Same problem.

I am plugging into WAN2 on UDMP.

LN1200 LAN light goes on and then off..

I plug LM1200 into my computer and it connects fine.

I have tried EVERYTHING I could think of. I disabled IPv6. I upgraded firmware. I plugged into WAN1. Nothing worked.

I need a LTE backup for my UDMP. This should have been EASY!!!!

Any help would be appreciated. I also have put in a support request. I hope I get some kind of response to this.

I believe this is a LM1200 issue and NOT the UDMP.

Thank You,

Pete G.
- Pmolter13
  Aspirant
  Sep 22, 2021
  I am also having the same issues with the LM1200 on Verizon but with a Tplink router.
  
  I was able to confirm with VZW that there should not be any issue connecting a DHCP router as the hotspot plan does not limit connections. I also have a support ticket open with Tplink to review the router logs showing the disconnect and reconnect cycling.
  
  However, I even tried an older Actiontec router left over from my previous ISP and that had the same issues once I connected multiple devices. This only seems to occur if the modem is connected to a router or hub. If it's a direct 1:1 connection, be it game console, pc or laptop, it works fine.
  - PeterG5000
    Tutor
    Sep 22, 2021
    Thanks for checking with Verizon. So we have pretty much ruled out everythign but the LM1200. I wonder if anyone has tried the Nighthawk M1 Moble LTE hotspot MR1100-100NAS? We need Netgear to fix this issue or I have to send this back. We are using this as the backup Internet in the case there is an outage with our wired carrier.
solah
Guide
Nov 09, 2021
I'm having the exact same issue and working through it now with support... my modem will randomly go through instances of the network connection repeatedly cycling (every 30s or so). I'm on verizon. The disconnect for each cycle seems to follow a instantaneous status change to the cell signal light, which may sometimes flash red a single time at the start of each cycle. When this was connected to a router with more detailed logging, the WAN gateway would flip / flop with each cycle. I have ruled out issues like the specific PC / router connected to the device, network cables, physical location of modem (different cities), etc. The problem is likely either 1) the unit is switching between cell sources, such as 3G vs LTE, and it's causing the modem to reset the network adapter or 2) the service provider verizon is sometimes switching between IPV4 and IPV6 and the modem / downstream devices aren't digesting it well.

It could also be a combination of the two factors above. I'm not savvy enough to force these external states upon the modem to narrow it down further, but I've mostly ruled out everything under my control on the device / network side.

If I'm able to catch another wave of resets with everything ready to go, I'm going to try to switch the Network Mode from Auto to LTE (to elimate its ability to switch between LTE and 3G) and also try setting the default PDP from IPV4V6 to just IPV4.
- JohnPeng
  NETGEAR Expert
  Nov 19, 2021
  solah wrote:
  
  I'm having the exact same issue and working through it now with support... my modem will randomly go through instances of the network connection repeatedly cycling (every 30s or so). I'm on verizon. The disconnect for each cycle seems to follow a instantaneous status change to the cell signal light, which may sometimes flash red a single time at the start of each cycle. When this was connected to a router with more detailed logging, the WAN gateway would flip / flop with each cycle. I have ruled out issues like the specific PC / router connected to the device, network cables, physical location of modem (different cities), etc. The problem is likely either 1) the unit is switching between cell sources, such as 3G vs LTE, and it's causing the modem to reset the network adapter or 2) the service provider verizon is sometimes switching between IPV4 and IPV6 and the modem / downstream devices aren't digesting it well.
  
  It could also be a combination of the two factors above. I'm not savvy enough to force these external states upon the modem to narrow it down further, but I've mostly ruled out everything under my control on the device / network side.
  
  If I'm able to catch another wave of resets with everything ready to go, I'm going to try to switch the Network Mode from Auto to LTE (to elimate its ability to switch between LTE and 3G) and also try setting the default PDP from IPV4V6 to just IPV4.
  
  We are investigating the issue right now that when using Verizon SIM card, sometimes, the data connection keeps dropping . Will get back to you soon after we find the root cause.
  
  Thanks
  - JohnPeng
    NETGEAR Expert
    Nov 19, 2021
    I think there are 2 different issues reported in this thread.
    
    1. LTE connection keeps dropping when Verizon SIM is used. This is being investigated. IT may be related to Verizon plan used.
    
    2. LAN connection dropped when connecting LM1200 LAN port to a WiFi router.
    
    Please check the issue you have and specify clearly whether it is LTE connection drop or LAN connection drop.
    
    Thanks
chibikegeek
Aspirant
Nov 18, 2021
This is happening to me as well.

Dual NETGEAR 1200s > TP-Link Omada > TP-Link Archer A10.

The Details:

Firmware Version: EC25AFFDR07A09M4G
App Version: NTG9X07C_20.06.09.00 Web
App Version: LM1200-HDATA_03.03.103.201
Hardware Version: 1.0
View from the Omada attached.

Peaks correspond to LINK DOWN, valleys to +/- 30 from LINK UP
- JohnPeng
  NETGEAR Expert
  Nov 18, 2021
  chibikegeek wrote:
  
  This is happening to me as well.
  
  Dual NETGEAR 1200s > TP-Link Omada > TP-Link Archer A10.
  
  The Details:
  
  Firmware Version: EC25AFFDR07A09M4G
  
  App Version: NTG9X07C_20.06.09.00 Web
  
  App Version: LM1200-HDATA_03.03.103.201
  
  Hardware Version: 1.0
  
  View from the Omada attached.
  
  Peaks correspond to LINK DOWN, valleys to +/- 30 from LINK UP
  
  Could you please confirm which carrier's SIM you are using, Verizon?
  
  Thanks
  - AaronWTCI
    Aspirant
    Nov 19, 2021
    I am also having the same exact issue, works fine plugged into a laptop. As soon as i plug into my sonicwall or other routing devices it drops out. updated firmware, reset to default. Doesnt work in bridged or router mode.
solah
Guide
Nov 22, 2021
Verizon

I put the LM1200LTE into router mode for the past week or so and it seems to have resolved itself (few short term instances vs. near constant and continuous cycling of the network / cell connector). However, I don't know if the underlying issue is the mode setting firmware (bridge vs. router) or the fact that "router" mode seems to force the parties to use IPv4... I suspect that IPv6 isn't playing nice between Verizon, the modem, and various downstream devices.

There are manual settings for IPv4 and IPv6 within the "Mobile" tab, but I was not able to solve or replicate the issues with those settings, nor was I confident that they were actually being applied correctly given what I was seeing elsewhere (IPv6 addresses were still being referenced and issued).

Others have commented on LTE dropout or LTE / WCDMA tower switching as a potential cause; I tested this in areas with clear LTE dropout issues and switching did not appear to correlate to the network cycling issues. However, these tests did not rule out an IPv6 issue with specific towers or connection types.
- twicken
  Aspirant
  Nov 22, 2021
  I'm also experiencing this issue on Verizon when using bridge mode, directly connected to a laptop through USB-C to ethernet converter. The issue goes way when I put the LM1200 in router mode.

Serdar

Aspirant

Nov 24, 2021

Having the same issue on Google Fi (which is actually T-Mobile, but a different APN).

LM1200 is set as Router mode or Bridge Mode: Bridge Mode
Carrier Name: Google Fi (on T-Mobile)
APN name: h2g2
IP Type: IPv4
Is LM1200 connecting to WAN backhaul: No
Router client brand and model: Netgate 7100 1U (pfSense Plus 21.05.1)
Broadband modem brand and model: N/A (Fiber ONT)

Logs from pfSense:

Nov 21 01:01:55 pfsense kernel: e6000sw0port2: link state changed to DOWN
Nov 21 01:02:17 pfsense kernel: e6000sw0port2: link state changed to UP
Nov 21 02:50:06 pfsense kernel: e6000sw0port2: link state changed to DOWN
Nov 21 02:50:28 pfsense kernel: e6000sw0port2: link state changed to UP
Nov 21 05:14:39 pfsense kernel: e6000sw0port2: link state changed to DOWN
Nov 21 05:15:01 pfsense kernel: e6000sw0port2: link state changed to UP
Nov 21 07:02:51 pfsense kernel: e6000sw0port2: link state changed to DOWN
Nov 21 07:03:13 pfsense kernel: e6000sw0port2: link state changed to UP

JinTu

Star

Nov 25, 2021

Serdar wrote:

LM1200 is set as Router mode or Bridge Mode: Bridge Mode
Carrier Name: Google Fi (on T-Mobile)
Router client brand and model: Netgate 7100 1U (pfSense Plus 21.05.1)

Logs from pfSense:

Nov 21 01:01:55 pfsense kernel: e6000sw0port2: link state changed to DOWN
Nov 21 01:02:17 pfsense kernel: e6000sw0port2: link state changed to UP
Nov 21 02:50:06 pfsense kernel: e6000sw0port2: link state changed to DOWN
Nov 21 02:50:28 pfsense kernel: e6000sw0port2: link state changed to UP
Nov 21 05:14:39 pfsense kernel: e6000sw0port2: link state changed to DOWN
Nov 21 05:15:01 pfsense kernel: e6000sw0port2: link state changed to UP
Nov 21 07:02:51 pfsense kernel: e6000sw0port2: link state changed to DOWN
Nov 21 07:03:13 pfsense kernel: e6000sw0port2: link state changed to UP

I am seeing the same thing on Verizon with pfSense, but was able to temporarily work around it by manually releasing and relinquishing the DHCP lease, then forcing a renew. Sometimes it requires doing this a few times for it to work, but once the link stabilizes, it stays up.

JohnPeng
NETGEAR Expert
Dec 02, 2021
Serdar wrote:

Having the same issue on Google Fi (which is actually T-Mobile, but a different APN).

LM1200 is set as Router mode or Bridge Mode: Bridge Mode

Carrier Name: Google Fi (on T-Mobile)

APN name: h2g2

IP Type: IPv4

Is LM1200 connecting to WAN backhaul: No

Router client brand and model: Netgate 7100 1U (pfSense Plus 21.05.1)

Broadband modem brand and model: N/A (Fiber ONT)

Logs from pfSense:

Nov 21 01:01:55 pfsense kernel: e6000sw0port2: link state changed to DOWN Nov 21 01:02:17 pfsense kernel: e6000sw0port2: link state changed to UP Nov 21 02:50:06 pfsense kernel: e6000sw0port2: link state changed to DOWN Nov 21 02:50:28 pfsense kernel: e6000sw0port2: link state changed to UP Nov 21 05:14:39 pfsense kernel: e6000sw0port2: link state changed to DOWN Nov 21 05:15:01 pfsense kernel: e6000sw0port2: link state changed to UP Nov 21 07:02:51 pfsense kernel: e6000sw0port2: link state changed to DOWN Nov 21 07:03:13 pfsense kernel: e6000sw0port2: link state changed to UP

For your case, since the connection is down and up in a certain intervals, please try to enable the Keepalive setting and set the interval smaller than what you see in the log. Some networks can reset the data connection if there is no data traffic for a certain period of time. Enabing Keepalive feature will keep the data connection alive. Please let me know whether this helps or not.

Thanks

txagg
Aspirant
Nov 28, 2021
Add another one to the list. I just purchased this device and with my USG Pro the connection drops about every 2 - 3 minutes when in bridge mode and then comes back with a new IP after about 1 minute, making the the connection basically useless.

App Version: NTG9X07C_20.06.09.00 - Confirmed
PRI version: 04.19 - Confirmed

Bridge Mode
Verizon
VZWINTERNET
IPV4V6 in APN, IPV4 in router
LM1200 LAN to USG Pro WAN1
Ubiquiti Unifi Security Gateway Pro
N/A
- Sommerfield
  Aspirant
  Dec 01, 2021
  I am having the same issue also using verizon, only connected to an orbi router. Has there been a resolution to this?
- JohnPeng
  NETGEAR Expert
  Dec 02, 2021
  Please try enabling Keepalive and set the timer as 1 minutes and let me knwo whether this helps or not. If not, I will need your help to capture some logs for the team to check.
  
  Thanks
  
  txagg wrote:
  
  Add another one to the list. I just purchased this device and with my USG Pro the connection drops about every 2 - 3 minutes when in bridge mode and then comes back with a new IP after about 1 minute, making the the connection basically useless.
  
  App Version: NTG9X07C_20.06.09.00 - Confirmed
  
  PRI version: 04.19 - Confirmed
  
  Bridge Mode
  
  Verizon
  
  VZWINTERNET
  
  IPV4V6 in APN, IPV4 in router
  
  LM1200 LAN to USG Pro WAN1
  
  Ubiquiti Unifi Security Gateway Pro
  
  N/A
  - Serdar
    Aspirant
    Dec 03, 2021
    Looks like that did it, thank you! It's been fine for ~18 hours now since I enabled KeepAlive. If it happens again, I'll update.
wellson
Aspirant
Dec 05, 2021
Popping on here to say that I was having similar issues. I'm on Verizon - also using a Netgear AirCard Antenna to supplement my cellular signal signal as I live in a state park - so relatively rural.

Seemed to me to be an intermittent issue, especially when several devices connected to the network. I am solely using the 4G LTE connection, no failover from hardwire. I'm using a TP-Link Archer A7 router as well.

Changing the keepalive setting didn't seem to make a difference but setting the modem to router mode has. Only have one question, how much data does the KeepAlive use? Like most of us I am throttled after xGB, and I'm a little alarmed to see when I connect to the modem manager that the device has supposedly used 1.7 GB in the past 25 mins. I'm continuing to set up devices, so I likely think that they are just syncing with my cloud services, etc. Just wanted to check to make sure that I don't need to readjust the KeepAlive. Let me know if I can be of any assistance in any way!
- AaronWTCI
  Aspirant
  Dec 06, 2021
  My keep alive was already set at the minimal interval of 1 minute. I checked this all again and added the address 8.8.8.8, and google.com to ping. The process is still the same, as soon as i plug my sonicwall in the port pulls a dhcp address and then the LM1200 wan port shuts down. Rendering the connection useless. So I then uplug the firewall and plug in my laptop. The port comes back up and I can pull another DHCP address from Verizon and surf the net without issue. Why does this seem to be happening with wan ports on routing devices?
  There are a lot of post here in this forum of people having similiar issues across multiple devices.
  - JohnPeng
    NETGEAR Expert
    Dec 06, 2021
    AaronWTCI wrote:
    
    My keep alive was already set at the minimal interval of 1 minute. I checked this all again and added the address 8.8.8.8, and google.com to ping. The process is still the same, as soon as i plug my sonicwall in the port pulls a dhcp address and then the LM1200 wan port shuts down. Rendering the connection useless. So I then uplug the firewall and plug in my laptop. The port comes back up and I can pull another DHCP address from Verizon and surf the net without issue. Why does this seem to be happening with wan ports on routing devices?
    
    There are a lot of post here in this forum of people having similiar issues across multiple devices.
    
    Please make sure you connect your sonicwall to the LAN port of the LM1200. The WAN port on LM1200 is for connecting your home broadband.
    
    Thanks
- JohnPeng
  NETGEAR Expert
  Dec 06, 2021
  wellson wrote:
  
  Popping on here to say that I was having similar issues. I'm on Verizon - also using a Netgear AirCard Antenna to supplement my cellular signal signal as I live in a state park - so relatively rural.
  
  Seemed to me to be an intermittent issue, especially when several devices connected to the network. I am solely using the 4G LTE connection, no failover from hardwire. I'm using a TP-Link Archer A7 router as well.
  
  Changing the keepalive setting didn't seem to make a difference but setting the modem to router mode has. Only have one question, how much data does the KeepAlive use? Like most of us I am throttled after xGB, and I'm a little alarmed to see when I connect to the modem manager that the device has supposedly used 1.7 GB in the past 25 mins. I'm continuing to set up devices, so I likely think that they are just syncing with my cloud services, etc. Just wanted to check to make sure that I don't need to readjust the KeepAlive. Let me know if I can be of any assistance in any way!
  
  Keepalive will use really small ammout of data. Please keep monitor the data usage. Please check what programs running on the PC used for setting up the device. The device itself doesn't have cloude services to use so much data within 25 mins.
  
  Thanks
kpbong
Tutor
Feb 08, 2022
I have the same UDM Pro setup with LM1200 on WAN2. My SIM is a Verizon BYOD data-only plan. The modem will connect and operate fine, until I swap the WAN interface in the UDM console to simulate a WAN failover. The moment the UDM Pro attempts to get a DHCP address, the modem will reset itself. I've tried both bridge and router mode with the same results.
- bbatty66
  Tutor
  Feb 09, 2022
  Sorry to add to the pile, but I am dealing with this exact issue and am hoping a resolution is close. I am in a rural location with only a single Verizon cell tower accessible, so I have no other options than to get this working somehow. I am using an LM1200 with a verizon provided SIM card, in bridge mode (after reading through the previous entries). I have an EnGenius EWS850AP connected for my WAP. When the system is running without a reset (for anywhere from a few tens of seconds to maybe half an hour) I can get net access through the wifi to my laptop or my cell phone. When I try and actually hook up the devices I need at this site (security cameras and miscellaneous controllers for items like heating systems) I can't successfully connect to the source router. I take that same WAP to a different location and connect it to a DSLAM, I can set up my devices just fine, which tells me that either my configuration on the LM1200 is incorrect, or somehow Verizon is filtering the IP traffic so that only a cell phone or a laptop PC can negotiate the connection.
  
  any advice is welcome. I don't have the specific IP transport knowledge that many use here, but I am a 30 year veteran digital hardware designer and at least familiar with the basics.
- jondaykoStage
  Aspirant
  Feb 11, 2022
  Same here, actually with a Ubiquiti USG (Unifi Security Gateway).
  Verizon 4G SIM, BYOD w/ a public static IP,
  
  I got the LM1200 in bridge mode, have the USG configured properly, but the moment it attempts to use the LTE network, which 99% of the time it will never actually establish a connection.
  
  If it does actually connect to the LTE network, it will only for a brief moment, then seemingly "restart" where you lose connectivity to the webpage AND loss of internet. So I can only assume the device is restarting itself. It will repeat this forever, but if you let it remain disconnected from LTE, you can login to the device and play with settings, it's just actually connecting is where it stops working.
  
  This is using the latest Unifi Controller, USG firmware, and latest Netgear firmware. Even after factory resetting it and just putting it into bridge mode, no dice.
  - kpbong
    Tutor
    Feb 11, 2022
    This is the same behavior I'm seeing. I'll add that if I log into my UDM Pro and add a static route on the command line:
    ip route add 192.168.1.5 dev eth9
    Then I can use the web interface and see that the device is connected, etc. When I swap the WAN interfaces and try to actually use the modem, it resets itself as you describe.

Forum Discussion

LM1200 repeatedly dropping link