Router has current version on it: FW_WRT1900AC_1.1.8.161917_prod.img The router itself loaded that during the last hard reset and simple setup cycle, yesterday.
Are you saying the router installed an invalid vesion by itself, without allowing human intervention? Does that speak volumes to NOT allowing the router to auto-update itself, if it can download and install an invalid version?
I will take down my network tomorrow night and do it again. Since take is the only option at point since the software has nuked itselfed when you turn off DHCP. This means:
1) HARD FACTORY RESET
2) Connecting the router internet port to internal network, that will give it DHCP and access to Internet.
3) Connecting a computer the switch ports on the back of the router
4) Accessing and preforming linksys simplicist setup, which includes autodownloading the curent version, becuase the password is set to random value for access to router, so you cannot use manual configuration.
5) sign back iin start the real configuration work
6) Reconfiguring wireless again to correctly have right SSIDs and fixing the naming and turning guest networks - that are on by default.
7) Changing the IP of the router to correct value, even though you cannot set the defualt route.
8) Turning of DHCP server on the router (this step nukes the software)
9) Disconnecting the router from internal network. Now connect the switch banks to firewall NIC, so the rest of the network has access to firewall too.
10) Reset some of the machines' NICs becuase of the netowrk going up and down multiple times detering the outage.
That will be a fun 30-45 mins.
Oh, I will check back before doing so in case you have other steps you wish to go through.
PS: I like Linksys Warranty: http://support.linksys.com/en-us/linksyswarranty