I had upgraded to the captioned version of DD-WRT successfully.
Router HW: Buffalo WZR-1750DHP
Method: Direct Upgrade without factory reset
Upgrade from version: DD-WRT 24865M v24sp2 (08/15/14) kongac
Result: Successful with minor issue
All setting can be remain unchanged after upgrade. However, the webui become cannot accessable. The lucky things is due to all (most??) setting can remain without issue so the router can keep operation, including nat to web, wifi access etc.
To resolve this issue, I had login to the router through putty ssh and find out the httpd is running with argument like this:
httpd -p 0
So this is an issue (and I think the only may be) after direct upgrade.
Here is the procedure to resolve this issue:
1. Use ssh client to connect the router lan address (if the router ssh was not enabled before upgrade or inaccessable.....I think the only way is 30-30-30)
command ps | grep httpd <enter>
to check the httpd running status
3. if the httpd is not running in desire port (80 or 443), run it manually by command
httpd -p 80 <enter>
to activate the router web server
4. Try to access the web ui with browser. If can see dd-wrt status page and can login to ui, you are a lucky guy
5. Go to Administration--> web access, uncheck http, check https, then save & apply
6. relogin web ui with https://<your router addess>
7. Like step 5, but uncheck https and check http this time, save and apply
8. reboot router, thats all.
BTW, is any benefit for this unit with 512MB ram ....since I compared with asus one this unit have more ram....but seems the build cannot fully utilise for this advantage.....