[Gugus]

Hello!

I just changed my router from an old TP-link unit to a WRT1900ACS v2, and I immediately flashed it to a dd-wrt build to be able to run vpn and such.
The TP-link had no issue with the ISP stability, and after a week of use, I had the Linksys unit crashing and blocking itself into an impossible reboot (power and esata light static, or power and orange isp lights). The only solution had been to power it off, wait for some time, and power it on again for it to boot.
I can switch from stock firmware (it installed automatically the 2.0.188450) to dd-wrt (I tested two builds until now, from april 2018, and now may 2017), but the issue came back.

I narrowed it down to using one device, cable or wireless, using a continuous stream (audio or video), making the router crash at some point. Temperature seemed normal (about 77 degrees) from what I observed, so I decided to eliminate my "custom" changes one by one. The crash happened again without a vpn running on dd-wrt, and at my surprise, it crashes while running the stock firmware as well... (even after using the reset button, and having the stock firmware being freshly set up)

So, considering having the stock firmware on partition 1, and dd-wrt on partition 2 (hat seems to be a little hard to get stable on this specific hardware), could dd-wrt interfere with the stock firmware execution?
Or do you think that this router is definitely faulty?

Thanks for the insights.

[SurprisedItWorks]

I've set up six of the WRT1900ACSv2 with dd-wrt so far, using at various stages BS builds 34315, 36698, 37736, 38159, and 39144. I don't recommend the first of those releases, but the other four have been great, and none of these routers have ever exhibited instability of any kind. I've been extremely happy with this router model, actually, so I'm suspicious that you actually ended up with a bad one (and your report makes me feel quite lucky that I never did), particularly because you saw the trouble on the stock firmware as well.

In the "it can't hurt to try" category, you might experiment with arranging things so that there's some airflow through the router for cooling just to see if things are different. I only operate one of these six routers with a cooling fan (drops CPU temp some 20 deg C), but as it's the one router actually available to me at the moment, I can't say for sure what the temps are without the fan. My memory is that it's more like 72 than 77, so perhaps you have one that runs hot.

[Gugus]

Thanks for your answer!
It's indeed strange that you got so many working and I have one acting so weird.
I tried to use a laptop support with fans to cool this router, and to my surprise I could run without issues on the stock firmware for a couple of hours (when it crashed with only two connected wireless devices yesterday after 1 hour or so).
Next up I installed the last BS dd-wrt build (39715), set up 2.4 and 5Ghz wireless, VPN aplet, USB power for the fan, and tried to use it with simultaneous streams and downloads.
It has been running fine for 4/5 hours now, and dd-wrt reports 64 to 68°C.

After searching about temperatures details a bit, I am still not sure if this router has a fan built inside, but people on the opendwrt forums have been pointing to kernel panics due to memory. It is possible that there is a memory overheat but it looks like it's something that happens on the whole manufactured line of ACS (at least), maybe due to a faulty memory stock.
Since I am in China right now and getting second-hand devices, I will run it like this and hope for the best. Now I know that the dd-wrt builds are stable, and which temperatures to avoid on this model. The more you know.

EDIT : only issue with this specific build I didn't see on previous ones is that the Wireless light indicator is always using the 2.4Ghz one for both bands being active now, the 5Ghz one is off. But I don' really care.

[SurprisedItWorks]

Great that you got things working!

This model does not have a fan, but apparently earlier ones in the series (the v1 of this model?) did have a fan. Yours is the first report I've seen of actual misbehavior due to lack of cooling, but I can't say I'm actually surprised.

Your experience will save others much grief, as now anyone having weird behavior from this model can be nudged (if they missed this thread) to try a bit of cooling.

Re current builds: what keeps me from trying them is that support for DNSCrypt has been either partially (just the enable button and the drop down) or completely (the underlying code) removed. For me that's a deal breaker.

You might want to edit your original post to add "[solved: temp issue]" or something at the beginning of the subject.

[Gugus]

It's really surprising to have this model not having a fan... I mean even the old TP-link I was using had a fan and was running in the same spot with direct contact to the surface underneath.

Anyway, you're right, I was waiting to see how this fix was going to hold with time, and since it has been stable since, I edited the title.

[ttowling]