Posted: Mon Sep 10, 2018 2:01 Post subject: Re: Stable build found! 28054 - updating wiki if good for 7
TechITEasy wrote:
The WiFi bug (intermittent disconnects OR connection remains but unresponsive and "no internet") has been plaguing my setup since I put DD-WRT on this router back in 2016. I've tried countless WiFi settings adjustments and numerous firmware versions including (but not limited to) 33492, 35531, 35916, 36808 - all with frustrating WiFi. So I dug through this thread's history to where I found the first reporting of the WiFi bug - November 2015. Applying the firmware version from before the bug, DD-WRT v3.0-r28054 big (10/30/15), has yielded stable results for 12 hours now of pretty heavy usage ... the longest span of stability I've experienced with this device! I'll update the wiki if this consistency remains for a full week of up-time and try to reach out to the development team to see if I can help troubleshoot the root cause.
Yes - that was my experience as well, everything was perfectly reliable up to a certain revision, which it looks like you located.
I am unwilling to revert to that years-old version due to the possibility that it may have security holes / bugs which were fixed in more recent versions in 2016-2018. (There were several high-profile bugs as I recall, not specific to DD-WRT but possibly to some underlying libraries it may use like SSL etc etc.)
I am strongly considering moving to pFsense due to the lack of support / follow-up to get this serious bug in DD-WRT (at least, with Broadcom chips & when using VAP / VLAN setups) fixed.
Some units are shipped with a buggy version. Latest from Asus is 1.0.1.9. The un-usuble one id 1.0.1.2.
Check by running "bl_version"
Ah-hah. I checked my CFE version
Code:
#nvram get bl_version
1.0.1.2
I will look into updating the CFE version, I'm sure I can find docs / how-to elsewhere. Thanks for the tip. Will report back here if that restores my WiFi to stable operation.
What version of CFE?
Some units are shipped with a buggy version. Latest from Asus is 1.0.1.9. The un-usuble one id 1.0.1.2.
Hmm, I have never done a CFE update before, only the usual firmware updates going from one version of DD-WRT to another.
Looks like there's real potential for bricking my RT-N66U, I don't want to risk that. I found some threads with partial information, and even a script (to run on the router) to do the update, but the script is compatible only with ASUSWrt, not DD-WRT firmware.
Here's one of the better threads I found, but I'm still nowhere near confident enough to try with the instructions & notes in it. Is it still necessary to go in & custom-edit the file to change region codes, MAC addresses, etc. in a hex editor before updating the CFE?
Appreciate it if anyone has links to recent known-good CFE update procedures for an RT-N66U w/ CFE 1.0.1.2, already running : DD-WRT v3.0-r35916 mega (05/11/18) on it.
Joined: 17 Apr 2014 Posts: 135 Location: SF Bay Area
Posted: Mon Sep 10, 2018 19:53 Post subject:
sampalazno wrote:
...
Appreciate it if anyone has links to recent known-good CFE update procedures for an RT-N66U w/ CFE 1.0.1.2, already running : DD-WRT v3.0-r35916 mega (05/11/1 on it.
NVRAM issue
IMPORTANT: DO NOT USE K2.6 builds if using CFE v1.0.1.3 (64K nvram) or NEWER!!!
At launch, the RT-N66U was limited to 32k nvram. However, CFE (bootloader) version 1.0.1.3 added 64k nvram support around April 2013, but was not compatible with DD-WRT firmware at that time. For details, see these forum links to historical nvram and 64K implemention discussions: Fractal comments and "RT-N66 CFE Thread"
This was resolved with DD-WRT K3X builds (kernel 3.x) which extended nvram to 64k, and can be used for any CFE version. It was eventually extended to 256k.
More historical info: http://charleswilkinson.co.uk/2012/12/22/dd-wrt-on-the-asus-rt-n66u-with-64k-cfe/
For newer CFE version updates and procedures see here: SNB Forums
I have no idea what this means and not sure where to look it up. I have flashed other routers to DD-WRT so I am not totally new to this, but in those cases it was just make sure you are on the right firmware and your hardware models match, and you are good to go. How do I find the answer to all that up there?
The router is on firmware 30043808120, what else do I need to find out? Is my first step determining if I have CFE v1.0.1.3 or newer? If so, where does one do that?
NVRAM issue
IMPORTANT: DO NOT USE K2.6 builds if using CFE v1.0.1.3 (64K nvram) or NEWER!!!
At launch, the RT-N66U was limited to 32k nvram. However, CFE (bootloader) version 1.0.1.3 added 64k nvram support around April 2013, but was not compatible with DD-WRT firmware at that time. For details, see these forum links to historical nvram and 64K implemention discussions: Fractal comments and "RT-N66 CFE Thread"
This was resolved with DD-WRT K3X builds (kernel 3.x) which extended nvram to 64k, and can be used for any CFE version. It was eventually extended to 256k.
More historical info: http://charleswilkinson.co.uk/2012/12/22/dd-wrt-on-the-asus-rt-n66u-with-64k-cfe/
For newer CFE version updates and procedures see here: SNB Forums
I have no idea what this means and not sure where to look it up. I have flashed other routers to DD-WRT so I am not totally new to this, but in those cases it was just make sure you are on the right firmware and your hardware models match, and you are good to go. How do I find the answer to all that up there?
The router is on firmware 30043808120, what else do I need to find out? Is my first step determining if I have CFE v1.0.1.3 or newer? If so, where does one do that?
If you have recent Asus firmware on it, you’ll probably have to flash it by putting it into recovery mode and using the mini cfe web browser or tftpd32. _________________ I am far from a guru, I'm barely a novice.
If you have recent Asus firmware on it, you’ll probably have to flash it by putting it into recovery mode and using the mini cfe web browser or tftpd32.
Okay so I wont doubt you and I will get that file, which makes things much easier, thanks, but, can you explain what all that stuff is on the FAQ page then? Why does it have all of these links to alternatives and other options when I just need this one file?
If you have recent Asus firmware on it, you’ll probably have to flash it by putting it into recovery mode and using the mini cfe web browser or tftpd32.
Okay so I wont doubt you and I will get that file, which makes things much easier, thanks, but, can you explain what all that stuff is on the FAQ page then? Why does it have all of these links to alternatives and other options when I just need this one file?
It’s old and outdated. I should clean it up. _________________ I am far from a guru, I'm barely a novice.
If you have recent Asus firmware on it, you’ll probably have to flash it by putting it into recovery mode and using the mini cfe web browser or tftpd32.
Hmmm... you bring up an interesting point. This router has a very recent firmware update and i'm wondering if that update would fix the Krack bug on the wireless controller and then allow us to re-install DDWRT?
This only says "fugget about it" and stay with the version before the Krack fix. Anyway i'll mess around with my JTAG and trace the CFE to see if this works.
Here is my story with N66U, version B1 with issues going downhill.
I've been using AdvancedTomato for year and half, last few days tried flashing DD-WRT.
First issue
Poor wifi. I expected that because prior to installing tomato i tried dd-wrt first and had same results
Tried dd-wrt.v24-28054_NEWD-2_K3.x-big-RT-N66U that someone here mentioned was before people started to talk about wifi issues.
Now wifi worked well but WAN wasnt getting DHCP from ISP (put on to test with tomato and johns merlin, that picked up WAN right away.) Hmmm
Then I try a bunch (including "BIG" varients)
Third issue: My setting stopped being stored.
I couldnt change wifi name or security, pressing save or apply just reloaded the GUI page with everything same. Then I noticed it wasn't just for wifi but for everything.
Shuffeling between tomato and merlin to see if device is still working, then back to dd-wrt next strange thing happened. I was able to apply SSID name change but then it stuck thru reflashes on dd-wrt end.
Tried firware restore to defualt, did button resets, used "erase nvram" and tried thru ssh. Nada.
After that final issue:
All dd-wrt's stop flashing completely , all version's i've tried before, aren't going thru anymore. No portal thru lan port, no light flash like normally at start up, no wifi light coming on during initializing.
put freshtomato on and take a brake
next i try mini k6 -- after reflash 192.168.1.1 isnt coming up but router lights flashed and wifi light is on
next i try 30/30/30 via wps button (cuz ASUS) then dd-wrt.v24-39956_NEWD-2_K3.x_mega_RT-N66U latest again
it fires up, but wifi SSID is tomatoe24 and admin isnt accepting defualt login nor the only login that i have been using
also usb light is on and i have not used usb's
another 30/30/30 still tomato's router name and ssid is retained,
hold reset for 5 second just to see what will happen, after restart, dead again,
and thats where I'm at now.
Broadcom BCM5300 chip CFE 1.0.1.2
EDIT: Reading more on CFE seems 1.0.1.2 is locking nvram write's and links for cfe_n66u-1.0.1.9.tgz from 2012 are dead by now. I thought dd-wrt and tomatoe overwrote CFE to support 64k but doing "nvram get bl_version" on tomato showed its not the case.
All I wanted was a functioning QOS (Fq_COdel) for low latency gaming while roommates TV was streaming. All tomato varients show me only "sfq or pfifo" (again i think because of locked CFE).
Most likely will need to buy another router and pair it up.
Joined: 17 Apr 2014 Posts: 135 Location: SF Bay Area
Posted: Sun Jun 09, 2019 21:12 Post subject:
1. Don't do 30-30-30 resets on the n66u, use the 'mega' builds unless you know why you need 'big'.
2. There's a Merlin v380.70 build https://asuswrt.lostrealm.ca/download in the 'legacy' section that should work since it *is* the asus firmware + patches.
3. Run the merlin+Asus to see if it suits: good wifi, no issues, and unfortunately no longer maintained. It enables the asus recovery mode mentioned in the N66U wiki.
... the longest span of stability I've experienced with this device! I'll update the wiki if this consistency remains for a full week of up-time and try to reach out to the development team to see if I can help troubleshoot the root cause.
on it.
'