How to free memory from OpenWrt

Hello Team,
So I got this device with Openwrt pre-installed. I am trying to install my custom ipk package but the memory is low. I am trying to remove some packages that are not important but when I delete them the memory remains the same.

The error says:

Only have 172kb available on filesystem /overlay

I have deleted a package with size 970kb but still the same error occurs and I can't see any free space created

Deleting packages from the installed image does not free any space, because of how OpenWrt handles the flash memory. You need to create your own image, for example with the image builder.


Thanks for the quick response. Which Image builder do you mean?
(Simply use goggle: Image Builder openwrt)


thank you for this link. I will work on this and give feedback.

I was unable to build my own Image because I could not find the model HL-WR865. That particular model is not on openwrt. I got this device from China with openwrt pre-installed.

Looks like an OEM-version of the ZBT-WE1326.
Compare the HW-specs of both devices. If they match, build for WE1326. And, be a brave guy, force the flash :slight_smile:

Hahahahaha. Ok I will try this. I bought about 10 of these devices and forced the flash of a D-Link DWR921 C3 on it and then I got this weird chinese page popping up. Lol. So I guess that router might be done for. I will bite the bullet and try this one. :joy:

ZBT for shure is the real manufacturer. However, they also do custom mods to their generic hardware. So there might be minor differences, i.e. size of RAM etc. But I doubt it.

Check out this ZBT
It has exactly the same CPU as the

So we reached out to the Chinese company that sold this to me to send the spec sheet.
This is the sheet.

Please let me know if there is any openwrt device you know that matches this. I will also check on my end.
I have also asked them for this information but i am waiting for their response.

Sorry, looks like I somehow got the wrong info about your router. There are quite a few devices supported, which use the 7620N. Although, when using goggle, I found the HL-WR865 running on a 7621. You might check the other 7620N-devices, which are supported. But I am rather pessimistic, you will find a matching device, because of 32MB RAM only on your router. You might ask your supplier, to provide THEIR build environment for you.

I was able to get the bin file from the supplier. Here is the link.

Please I will like to know the openwrt supported device that was targeted or how to remove unnecessary files on it so I can have space to install my software on it.

Build-Environment is required, not just the image itself.

Alright. I will

I was able to get the device they are targeting. It is a ZBT-WE826. I have been able to flash the device and installed my software. But I am getting an error when I try to run the software,

Error relocating /usr/lib/ secure_getenv: symbol not found

Maybe I will create a new topic for this one. Thanks for all the help guys

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