I have a NB-IOT device which is running with openwrt,
it‘s working just fine with hotspot provided by Phone with Android 8，
but when it connect to those hotspot provided by Android 9，
Here comes a problem，
after the hotspot was restarted accidentally,it can‘t automaticly reconnect to the old hotspot network，
I tried in some different android phones, Xiaomi, Oppo, Vivo, different android 8 or 9,
have the same problem in all android 9 phones,
I may found the cause, I guess,
under android 8, the hotspot IP will NOT change, nomatter how many times you restart the hotspot,
so even the phone was rebooted, My device still CAN reconnect to the hotspot without any manual operating.
But in android 9，
if you restart the hotspot，your old SSID will be arranged a new IP，a totally random one,
form 192.168.43.1 to 192.168.43.255，and it won't be your last IP，I am sure.
and the IP is different every time you restart hotspot,
(IP adress doesn't change in WIFI mode, wlan0, only changes in hotspot mode）
then my device can‘t reconnect to this hotspot automaticlly,
The device needs reboot to reconnect, and I don't want it to,
I am a newbie here , my device is using a 4M firmware，MIPS OpenWrt Linux-3.18.29 version,
Am I need to upgrade the linux kenel to the lastest version? Is this upgrade can simply solve my reconnetion problem?
Or Just need to modify the source code?and how? Is there a patch?
any help？thanks...
That doesn't make a lot of sense since any re-connection will trigger a new DHCP negotiation which would get the new IP address. What does the log show?
Is this a manufacturer's build? It's either that or a very old official version. This forum expects that you will be running a recent official build available on downloads.openwrt.org or built yourself from the open source code.
If I clone the code from the github， then make a new firmware，
It will be a totally my version one.
I am afraid this my new firmware could not running on my devices without errors,
cause I have no idea about the code where my manufacturer has changed.
I do NOT have the source code of the firmware now running on my device，
I only have the firmware，a bin file，
and I know how to unpack and repack the bin file，
Is there any chance I could update to the newest version, only by replacing some files in the unpacked bin file?
which files should be replaced to update？
Why do you need the source code to an old router firmware?
This is dangerous and likely impossible given the numerous files that would need updating. Of the many folks who've attempted this, I know of no one having success.
Thanks a lot，
I have downloaded the last Stable Release version，openwrt-18.06.2-ramips-mt76x8-miwifi-nano-squashfs-sysupgrade，
But my NB-IOT device is a custom hardware, not got from final market,
so before I flash it, anyone got anything to say?
this is the time...wish me luck。。。
I check the bin firmware， it is made by openwrt chaoes camler branch，so I think maybe I can replace it with the main branch，where can I find the chipset info in the unpacked bin file？
ok ，I got the info，the wifi chipset of my NBIOT device is MTK mt7688，looks like be supported by OpenWrt，It is in TOH， so The Chance I got it working is 80% now？
Nope, doesn't make your chances any better. Dozens of ways it could be wired up, dozens of ways the flash might be partitioned, the flash might be anything from 4 MB or below (which is unworkable) on up.
Is it cheap enough that you can, without hesitation, assume that it will be destroyed and unrecoverable?
If you even took a moment to think about it, no, don't do it.
Until you've got a boot log and partition information, you should assume it will be unrecoverable if you try.
ehhhhhhhhh
I am comparing the file between my device and the official release，
and I found mtk source code on their website，
hope I could find some useful info.
, my device is using a 4M firmware，MIPS OpenWrt Linux-3.18.29 version,
