Found why inadyn had exited on some systems. If the modem is down, a DNS lookup to the router can return an address of 192.168.0.1 for the dyndns.com server. inadyn then gets an incorrect response back from 192.168.0.1 and exits. Modified the code to sleep and continue.
Also, in a similar way, nidas could get a bad address for eol-rt-data. When it sends a UDP packet to the wrong address it gets a "connection refused", but continues to try that same address. New code will do a new DNS lookup.
Installed the new inadyn and nidas on all systems between 17:30 and 18:15 MST Nov 19.