So far so good for all SSH, OpenVPN, PPTP, Wireless, Router etc. features and functions..
From my experience, DD-WRT different versions do have different bugs / problems, for me
1) dd-wrt.v24-18946_NEWD_openvpn__jffs_small.bin (07-Apr-2012) tested to be fail in OpenVPN. Even after successful connection with OpenVPN server, the client's request could not be routed to WAN/internet.
2) dd-wrt.v24-17990_NEWD_openvpn_jffs_small.bin (08-Dec-2011) tested to be fail in OpenVPN. Even after successful connection with OpenVPN server, the client's request could not be routed to WAN/internet.
3) Therefore, dd-wrt.v24-17084_NEWD_openvpn_jffs_small.bin (17-May-2011) is the most-updated firmware that tested to be fully working in OpenVPN and general AP/Router functions for me .
It impressed me that a more updated version does not necessaily mean less bugs/problems.
Suggest you use a broadcom based router to flash with version DD-WRT v24-sp2 (05/17/11) vpn-small - build 17084M NEWD Eko作者: Skypeus 時間: 2013-12-15 14:09
This DDNS function of DD-WRT is actually uploading/updating/posting the renewed/latest WAN IP address to your selected DDNS service provider for your router's URL. Your OpenVPN client can then pick-up the renewed (or the latest) IP address from the DNS server and use the renewed (or the latest) IP address to access your router.
Therefore, you can first test accessing your DD-WRT router using your router's WAN IP address first (ie. use WAN IP address, instead of URL for your router in your client OpenVPN configuration file) and see if you can access properly. If you even cannot access using the router's WAN IP address, you should first begin troubleshooing why it cannot.
I worry this part even cannot works.
After you can access your router from client using your router's WAN IP address in your client OpenVPN configuration file, you can then check your DDNS service provider's webpage for your router's URL to see if any changed WAN IP address for your DD-WRT router can properly be updated at your DDNS service provider.
To trigger this, you need to change the WAN MAC address of the DD-WRT and restart the router.作者: Skypeus 時間: 2013-12-16 15:17
This DDNS function of DD-WRT is actually uploading/updating/posting the renewed/latest WAN IP addr ...
tomleehk 發表於 2013-12-15 15:03
DD-WRT sends the request to the specified DDNS service provider immediately when it notices a change of WAN IP address during boot-up. The consequent steps as well as time-to-wait are not controlled by DD-WRT.
I use DynDNS for my DDNS and I found it just takes a few minutes (e.g. less than 5 minutes) to make everything effective.
Therefore, if you need to wait a much longer time, I believe it is because the updating of your URL to the China DNS servers is rather slow.