Netgear WPN824N loses configuration after reboot

Hi All,

I have a Netgear WPN824N that I pulled out of storage that has LEDE 17.01.4 successfully installed on it. I am experiencing a problem however where after rebooting the device it appears that it has been reset to a firstboot state where not even the root password is set up. What might be wrong with it? Although it appears to be OK did I mess up something during the flash? Let me know what more information I need to provide.

Thanks,
Networkingisneato

With a 4 MB flash device, it's quite likely that you simply don't have enough flash left for the overlay - in which case an emergency overlay is spawned over tmpfs. Look in dmesg and "df -h" for clues.

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So I guess I'm better off reinstalling the OEM netgear firmware if I'm not looking for a specific application in LEDE? If I was OK working with this device only through SSH, how could I set this up so that it did save its configuration files?

You can still trim down the firmware down to your needs, but it's getting tight for 4 MB flash (especially with kernel 4.14 in the future). The easiest approach is indeed to remove luci, but this requires either using the buildroot approach and compiling a stripped down firmware from source (this gives you more freedom to (de-)select features) or the imagebuilder, which uses binary packages to repack the firmware; both approaches are described in the wiki.

The easiest test for now would be to sysupgrade to a master snapshot, as those don't include luci to begin with and therefore are a bit smaller than release builds.

I would like to try a sys upgrade to one of the master snapshots like you recommended but beyond the CPU being an AR71 I don't know where to go or what to download. Could you provide a link to a perticular download that should work for me?

Thanks,
Networkingisneato

I'm having the same problem. Thank you slh for the clues. Maybe this should get into the wiki page for the device.

I found a "tiny" snapshot in https://downloads.lede-project.org/snapshots/targets/ar71xx/tiny/. I'm flashing by serial and the factory firmware is already replaced, so I'm using the sysupgrade version.

Here's the output of df after installing lede-17.01.4-ar71xx-generic-wpn824n-squashfs-sysupgrade.bin

Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/root                 2304      2304         0 100% /rom
tmpfs                    14088        44     14044   0% /tmp
tmpfs                    14088        48     14040   0% /tmp/root
overlayfs:/tmp/root      14088        48     14040   0% /
tmpfs                      512         0       512   0% /dev

Notice the overlay is over a temporary copy of the root filesystem. There are also clues in the output of dmesg |grep jffs2:

[    9.087080] mount_root: jffs2 not ready yet, using temporary tmpfs overlay
[   24.652300] jffs2: Too few erase blocks (4)

After installing wpn824n-squashfs-sysupgrade.bin, here's the output of df:

/dev/root                 2048      2048         0 100% /rom
tmpfs                    13736        56     13680   0% /tmp
tmpfs                    13736        32     13704   0% /tmp/root
tmpfs                      512         0       512   0% /dev
/dev/mtdblock5             320       216       104  68% /overlay
overlayfs:/overlay         320       216       104  68% /

Notice the overlay is directly on top of a partition of flash. Also, here is what is reported about jffs2 in dmesg:
[ 9.098058] mount_root: switching to jffs2 overlay

Finally, with the tiny image, changes to the configuration files are saved between reboots. Yay! I'm just stuck doing command-line configuration now. At least this is experience to give me confidence to switch to openwrt with my better router later.

I added the snapshot firmware images with the new tiny subtarget to https://openwrt.org/toh/netgear/wpn824n.

I've built an image for the WPN824N that runs 17.01.7 with no issues. You can upgrade directly from a previous version of OpenWrt using the sysupgrade .bin file.

This image includes LuCi (GUI), IPV6, SQM, and PPP. A build manifest is available in the download folder.

If you end up installing, please let me know how it works for you. I don't have a WPN824N to test it on directly - but it runs great on my identical hardware, the WNR1000V2.