Router: Linksys WRT1900ACS
I have recently set up extroot to use an 8Gb flash drive and I'm looking for some advice on useful things that can be done with this new found functionality. Obviously, the increase in storage capacity for software packages is a win, but I would like to do a little more tweaking to streamline things (We are dealing with Linux, after all!)
For example, I have already modified the /etc/opkg.conf so that the opkg-lists are now stored on the USB filesystem instead of /var, which helped free up a few hundred kilobytes of ram.
Another example is that I use collectd to track statistics, and by default, collectd and rrdtool store their files in /var/etc, and /var/rrd* respectively, but I would like to move those to the overlay as well, but I am having trouble figuring out where the /var/etc/collectd.conf is generated from... Maybe i'm wrong, or confused, but it is my understanding that everything in /var is wiped on reboot and re-generated from other configs, yet the config file is located at /var/etc/collectd.conf, so I am assuming that this file is created from settings stored somewhere else?
I am also interested in understanding extroot a little deeper for the purposes of backup and firmware upgrades.
I would like to be able to create a sort of tiered system. Basically I would like to have the ROM contain all the same setup and configuration as the extroot partition for certain critical services such as DHCP assignment, Wireless security, etc, so that if the extroot partition is not available, the rom filesystem contains everything necessary to keep things running. I guess I'm asking how to migrate some of my configuration backwards from the extroot onto the ROM.
I have found a bit of documentation regarding firmware upgrades when using extroot, and I understand that special precautions are needed when using extroot, and that when I do upgrade the firmware, I will need to re-create the extroot setup manually, because it will not port seamlessly across different revisions. But there are some scary warnings stating that bricking is possible... Does anyone have any clarification on the upgrade process?