I am new to Openwrt and managed to flash my new Linksys 1900 acs with Openwrt and set it up with my ISP. But after running for a short time (a week or two) I did something which resulted in a system crash on my router and when it rebooted, the only OS offered was the stock Linksys wrt. That was back in November 2019 and since then I have not been able to spend time on resolving this problem so I can no longer remember all the details. However I now have some time so I want to get it going again and need a bit of help.
Is it likely that the OpenWRT installation is bricked? Is this the reason that the router is now booting into the stock WRT?
If OpenWRT might have survived how do I get the router to boot from that partition again? I have tried to ssh into the router but there is no access.
If it is likely not to have survived how do I go about testing the partition and then re-install openwrt onto the original partition again.
Finally should I aim to keep the stock WRT partition as a back up or install OpenWRT on that too?
Thanks in advance for any help yyou may be able to give
Your router has two firmware partitions. If booting openwrt on the active partition fails repeatly, it falls back to the other partition. When you flash a newer firmware, it get installed on the other partition. So, you always the recent (working) partition as a fall back. You can manually switch the active partitions as described here.
In your case, since your router fell back to the Linksys stock firmware, your openwrt setup on the other partition is most likely bricked and fails to boot. You can try to manually switch to that partition, but I would guess you won't get openwrt to boot that way and the router will fall back to stock.
I would just reflash openwrt from stock as if you did this the first time. That way, the (most likely) broken openwrt installation gets replaced. But also all your openwrt configuration changes are gone.
I wouldn't bother replacing the firmware on the other (non-active) partition on purpose. It will happen when you upgrade your working openwrt installation, because then that other partition will get flashed.
Or there were simply power issues, making the bootloader merely believe OpenWrt had crashed; e.g. PSU yanked from the socket (3 times) or an unclean power outtage, respectively power coming back in a kind of stuttering way.
Thanks for your reply. Very helpful. I have reinstalled openwrt and I now have that running on the router. I now need to get it all set up which I may have to leave until tomorrow now. I will see how I get on and may come back for some more help when needed, if that is okay.