I'm currently researching my home router (D-Link 2760-U) which has a (kind-of) proprietary ISP firmware. What I'm trying to achieve is understanding how the router is persisting it's configuration settings across reboots.mount output:/dev/mtdblock0 on / type squashfs (ro,relatime)/proc on /proc type proc (rw,relatime)tmpfs on /var type tmpfs (rw,relatime,size=420k)tmpfs on /mnt type tmpfs (rw,relatime,size=16k)sysfs on /sys type sysfs (rw,relatime)I did nvram show and it does contain some wireless configuration such as the encryption in use, wireless modes, pre-shared key but that's about it. Obviously the router has other configurations (such as DNS, PPP, Port forwards etc) that must be stored elsewhere. As it can be observed, all mounted filesystems are volatile and thus configuration cannot be stored in them.Where can the information be saved besides filesystem and NVRAM? How do I go about finding this out?
How can I figure where my router stores it's configuration across reboots?
linux;firmware;embedded
I have played with at least one (not a D-Link) Linux-based router that stored its configuration in a bare mtd partition and accessed it using a proprietary binary.  It compressed the data using LZMA or something but within that, you could see passwords in clear-text (not good!)D-Link actually have a very good GPL source code system, go to http://tsd.dlink.com.tw/downloads2008list.asp?SourceType=download&OS=GPL and type in 2760 and you can download the entire buildroot and source for that router.Even if they happen to use some non-standard proprietary mechanism for saving configuration, you should be able to get some idea of where it is hidden from examining the GPL sources...