I have a WNDR3800, flashed trunk version of OpenWRT, and then did a
sysupgrade -r from previous working backup on the same machine. After reboot everything is normal (since many packages are not installed), but Once I try to connect to it via SSH it reports:
Aiee, segfault! You should probably report this as a bug to the developer Connection to 192.168.3.1 closed.
After that I put it in failsafe mode, connected via
telnet and tried severial commands:
root@(none):/# /etc/init.d/dropbear start root@(none):/# mv: can't remove '/etc/dropbear/dropbear_dss_host_key': Read-only file system mv: can't remove '/etc/dropbear/dropbear_rsa_host_key': Read-only file system chown: /etc/dropbear: Read-only file system chmod: /etc/dropbear: Read-only file system Failed to connect to ubus root@(none):/# mount_root root@(none):/# /etc/init.d/dropbear start Failed to connect to ubus Failed to parse json data: unexpected end of data interface lan has no physdev or physdev has no suitable ip Failed to connect to ubus root@(none):/# ifconfig eth0 Link encap:Ethernet HWaddr 46:94:FC:XX:XX:XX inet addr:192.168.1.1 Bcast:192.168.1.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:2059 errors:0 dropped:531 overruns:1 frame:0 TX packets:188 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:371693 (362.9 KiB) TX bytes:18693 (18.2 KiB) Interrupt:4
Also I tried
firstboot with or without
mount_root, in both cases it stucks and does nothing.
Since dropbear refuse to start, I am unable to configure anything. Is there any way I can revert to default settings or flash another version of firmware?
You can try the recovery method using TFTP as described for the WNDR3700 here (it also applies to the WNDR3800). If this does not work, you can use the serial console as a last resort to directly talk to the U-Boot bootloader and instruct it to load a firmware image using TFTP. Hope this helps.
Unfortunately, the recent OpenWRT distributions seem to be broken in many ways. They change too many things too fast. Actually, I found your question while looking for known errors of the json parser of this
ubus thing in latest “stable” 15.05 (couldn’t find anything in the OpenWRT forum/ticket system related to that particular error), which breaks something trivial as the firewall start/stop script and other commands like for example
As for me, I will go back to 12.09 for now, which is the latest really stable version for my platforms (Netgear WNDR3700, TP-Link WDR4300, PCEngines Alix). As a long-time user of OpenWRT (10 years) I usually try to fix errors first before reverting back to older versions, but due to the lack of documentation of the new features it does take much too much time to dig into this new and (IMHO) very complex framework.