DD-WRT Broken Again

After resolving my bricked Asus RT-AC66U router, I wanted to return to getting OpenVPN running. With the help of another person, A.S., I found a few cracks in my previous approach and thought I might succeed this time. Possibly without black magic or voodoo.

I connected my Lenovo Thinkpad T400 laptop to an open VLAN port on the router and selected the appropriate NetworkManager configuration.


I then tried connecting to the router’s wireless guest connection.


I powered on my HP desktop, which is connected to its own VLAN.


I monitored the log output as I connected. There was no DHCP lease being provided.

Everything was working some days ago.

I started searching the DD-WRT forum and found one possible reference, although with an Asus RT-AC88U router. The description sounded similar to my experience. As often is the case in the DD-WRT forum, no solution was provided and no meaningful discussion.

I am using version 34080, released December 14 2017. According to the original poster in the forum thread the DHCP breakage is observable in version 33986. There was no information if the bug was introduced in previous versions.

As I discovered previously, the .profile breakage is observable in at least version 31899 (April 24 2017) and seems to have been resolved sometime around version 33675.

Looking through the firmware releases, the only theoretical choice to avoid both a broken .profile and DHCP seemed to be version 33772, released November 16 2017.

The routine is now familiar. Backup all settings and hold my breath as I apply the new firmware version.

No bricking this time. The .profile file worked but DHCP remained broken.

There is no version 33679 (November 4 2017) for the RT-AC66U. I would have to try version 33607 (October 25 2017).

Same result, the .profile file worked but DHCP remained broken.

Next was version 33555 (October 20 2017).

Same result.

Moving backwards one version at a time would be futile because of the broken .profile file. I jumped several versions to version 31899 (April 24 2017). Of course, I already knew that would break sourcing the .profile file.

DHCP remained broken.

One more try, all the way back to version 30826 (November 1 2016), where I knew everything had previously worked.

Miracle of miracles. Both the .profile file worked as did DHCP on both the VLANs and guest wireless.

Basically, I was back to where I started several days ago.

One caveat about these older versions is there is no KRACK patch. I am not overly concerned about that because the router is on a private network in an isolated home in a rural location.

The frustrating part of this saga is the beta channels seem to be the only way users receive appropriate security patches — if any. There is no official release. Using the DD-WRT download page shows the “current” release is v24 preSP2 [Beta] Build: 21061, dated September 7 2017. Presumably this is based on the beta firmware released March 25 2013. A date of September 7 2017 means this version is not patched for KRACK, assuming a patch is needed. As far as I can tell, this version is not patched.

There is a significant file size difference between the “current” version (18 MB) and any of the recent beta releases, such as 24 MB for version 30826 that I am now using. I am leery of using this older, smaller version because I don’t know what features I will lose. Worse, being labeled “v24” means I would have to reconfigure the entire router from scratch.

A few hours or so later and I still had not started testing OpenVPN, which is where this story began. I am weary of this breakage.

For now I will live with an unpatched firmware. At least I have everything back to functional. I need a working router with decent wireless in the house.

I am thinking I should start reading about different firmware and professional routers. Yes, DD-WRT is free/libre software. Developers likely are doing their best most of the time. Just don’t ask me to recommend DD-WRT.

Posted: Category: Usability Tagged: DD-WRT

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