Orbi LBR20 How-To / Megathread

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hazarjast
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Re: Orbi LBR20 How-To / Megathread

Post by hazarjast » Thu Nov 19, 2020 12:35 pm

cabegol wrote:
Wed Oct 21, 2020 8:06 am
I'm sorry for the very ignorant question, can somebody help me with the first steps to create the ttl_mod file? Thank you!
The code is provided in the OP inside the code block with the "iptables" commands. Please let me know if you are still unclear on any point.

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Re: Orbi LBR20 How-To / Megathread

Post by hazarjast » Thu Nov 19, 2020 12:47 pm

USMCDoc wrote:
Thu Oct 29, 2020 4:40 pm
Hello gang,
Ive been a lurker on this sub for the past few months so still trying to learn. Ive been using the lbr20 on att with no problems until recently so I made the switch to tmobile through nolimitdata. So far no success with this sim. I started my research last night on using telnet/putty. Would any of you be willing to point me in a direction that might get this to work? I appreciate all of the knowledge you have shared on this sub. Thanks!
Sorry for the late reply to this; I have not been on this thread in awhile. "nolimitdata" looks like some unauthorized reseller of T-Mobile consumer plans (usually One or Magenta phone or tablet lines). SIM from such plans will only work in a device with an IMEI TAC that identifies it as a phone or tablet (depending on the what it is provisioned for). Given the LBR20 has a TAC that identifies it as a data only device T-Mobile likely blocks it from connecting.

The workaround for this is not hard on Quectel modems like the one inside the LBR20 but I will not explain any further here as the workaround actions could a legal quagmire depending on your country's laws that deal with making modifications to RF equipment serial numbers. There is a very obvious clue in one of the code blocks of the OP though, if you should choose to pursue this further.

hazarjast
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Re: Orbi LBR20 How-To / Megathread

Post by hazarjast » Thu Nov 19, 2020 12:50 pm

brandorc wrote:
Thu Oct 29, 2020 4:54 pm
Thanks so much for all the useful information - this thread is great! Apologies for my ignorance, but would it be possible for someone to post a walk through for a newby in creating these mod script files to edit the ttl? I'm able to make it into putty, but I'm just absolutely lost on how to actually create these scripts. Thanks so much for any help! You guys rock!
The script code you are looking for is in the code block with the "iptables" commands in the OP. Please let me know if you are unclear on some point regarding this. You will have to use the text editor 'vi' to create/edit the mod script once you have telnetted into the device. I will not cover 'vi' usage here but there are plenty of guides/tutorials on this that can be found with a simple google or youtube search.

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Re: Orbi LBR20 How-To / Megathread

Post by hazarjast » Thu Nov 19, 2020 12:53 pm

umbighouse wrote:
Mon Nov 09, 2020 3:15 pm
+1 for me too. I'd like to get the ttl_mod script file setup and running too.
The code for this is in the OP; second code block with 'iptables' commands in it. Please let me know if you are unclear on any point. If you are not familiar with creating and editing text files under Linux I would suggest looking up a tutorial on the 'vi' text editor (which is what you would use to create/populate the mod script file on the LBR20 once you telnet into it).

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Re: Orbi LBR20 How-To / Megathread

Post by hazarjast » Thu Nov 19, 2020 1:07 pm

Since I had a couple queries on interpreting the +QENG output for 'servingcell' and 'neighbourcell' when preparing to lock a specific cell site, I will post a consolidated copy of my replies here for the benefit of the whole class ;)

In general, most of the AT command output definitions can be found in the Quectel documentation for the EG18 modem below (this is the modem inside the LBR20; pg. 79 provides details surrounding +QENG 'servingcell' output):
https://www.quectel.com/UploadImage/Dow ... l_V1.0.pdf

Be aware that some AT commands are undocumented in the product-specific manual, such as +QNWLOCK, as they are considered "engineering" or "unfinished" commands not for use by end users. But still we can find info on them and their syntax in Quectel forums etc. via references to sister products (in this case the EG12):
https://forums.quectel.com/t/eg12-and-f ... ature/4619

Let us take some example output from +QENG 'servingcell':

Code: Select all

+QENG: "servingcell","NOCONN","LTE","FDD",310,260,6C150D,222,1125,2,4,4,A6F7,-81,-8,-54,21,0,90,-
Applying the EG18 'servingcell' legend to the example output above reveals the following details about the currently connected cell:

MCC = 310
MNC = 260
CELLID = 6C150D (note that this is a hexadecimal value; decimal value used on cellmapper etc. would be "7083277")
PCID = 222
EARFCN = 1125
FREQ_BAND_IND = 2
UL_BANDWIDTH = 4 (0 = 1.4 MHz 1 = 3 MHz 2 = 5 MHz 3 = 10 MHz 4 = 15 MHz 5 = 20 MHz)
DL_BANDWIDTH = 4 (0 = 1.4 MHz 1 = 3 MHz 2 = 5 MHz 3 = 10 MHz 4 = 15 MHz 5 = 20 MHz)
TAC = A6F7 (I believe this is a hex value as well; decimal value would be "42743")
RSRP = -81 [dB]
RSRQ = -8 [dB]
RSSI = -54 [dB]
SINR = 21 [dB]
CQI = 0
TX_POWER = 90 [dBm]
SRXLEV = - [dB]

If you use +QNWLOCK on the Orbi to lock to a specific cell (tower) I have found it is not persistent across reboots (i.e. no need for a factory reset to clear the setting). Thus, in my setup, my bootstrapper script executes it after each restart because I want it to lock the same cell each and every time when the device is rebooted.

Be aware that "neighbourcell" output fields and format differs so be careful when using it to obtain any reference CELLID and PCID because they may appear in a different order or format (hex vs. decimal etc.). Legend for "neighbourcell" output can be found on page 80 of the EG18 PDF I linked to above.


Hope this expanded detail was helpful to folks.

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