[Solved] - Weird Temporary Network Failure.

[kdemeoz]

Hello

Something very weird just happened within the last hour, on my Tower [ethernet cable connection direct to modem].

1. I had been online for hours as usual, all was fine [& Maui/Tower has been performing nicely for quite a while now, after my previous dramas per other posts].
   
2. Suddenly i lost all internet access.
   
3. Glancing at my modem, i saw that its Internet LED had gone off, & after a few seconds, so did its DSL LED.
   
4. Soon after this, the DSL LED came on again, & a little later, also the Internet LED was back.
   
5. I was irritated but not alarmed at the interruption, [falsely] assuming it had been a momentary blip by my ISP.
   
6. However i found that Tower continued to have no internet access [not via browser, & neither in Konsole pinging 8.8.8.8]
   
7. I ran my bash script to refresh Maui's network connection. This gave every indication of success [as is usual for it], but i still had no internet access.
   
8. I power-cycled the modem [twice], & did more script-refreshes of the network manager... still no good.
   
9. I contacted my ISP to report the fault. They said there was no problem at their end, & tried to get me to do all the things that i had already told them i had done [why don't they ever listen?]
   
10. At this point the telephone connection dropped out whilst they had me on hold [grrr]. Before i called them back, i decided to test the internet connection independent of Maui & Tower. I grabbed my Android tablet, started its WiFi connection to my modem, & was shocked to see that it immediately connected & went online. 
    
11. Realising that this proved the fault was not my ISP, but something with Tower / Maui, I rebooted Tower.
    
12. Internet connectivity was once again ok, after logging in.
    

This left me feeling very embarrassed with my ISP, once i realised the fault lay with Maui & not them (i even rang them back to apologise]. 

Any ideas for this weird occurrence pls? WHY did Maui get so confused when the modem briefly lost its DSL connection, & then WHY did my usual refresh of network connectivity not help (it usually does]? WHY was a reboot then the necessary nuclear option?