Thanks for putting this together! I had been looking for something like this to get me started with Ethereum...

I've been going through the walkthrough and seem to have hit a snag. I have alice, bob, and lily all initialized and connected to each other as peers to form a three-node network, and have tried to have alice start mining. The "Generating DAG in progress" completed after 13 minutes (not 1 minute as you said it should, though I'm running Ubuntu on a virtual machine on my not-that-fast Surface Book which may explain this. After it completes, I see this message in the console:

DEBUG[09-08|12:27:59] Recalculated downloader QoS values rtt=20s confidence=1.000 ttl=1m0s
INFO [09-08|12:28:03] Generating DAG in progress epoch=0 percentage=98 elapsed=12m39.760s
INFO [09-08|12:28:09] Generating DAG in progress epoch=0 percentage=99 elapsed=12m46.488s
INFO [09-08|12:28:09] Generated ethash verification cache epoch=0 elapsed=12m46.499s
DEBUG[09-08|12:28:09] Failed to load old ethash dataset epoch=1 err="open /home/xxxxxx/.ethash/full-R23-290decd9548b62a8: no such file or directory"
INFO [09-08|12:28:13] Generating ethash verification cache epoch=1 percentage=82 elapsed=3.088s
INFO [09-08|12:28:13] Generated ethash verification cache epoch=1 elapsed=3.636s
DEBUG[09-08|12:28:19] Recalculated downloader QoS values rtt=20s confidence=1.000 ttl=1m0s
DEBUG[09-08|12:28:39] Recalculated downloader QoS values rtt=20s confidence=1.000 ttl=1m0s
INFO [09-08|12:28:59] Generating DAG in progress epoch=1 percentage=0 elapsed=22.150s
DEBUG[09-08|12:28:59] Recalculated downloader QoS values rtt=20s confidence=1.000 ttl=1m0s
DEBUG[09-08|12:29:18] Couldn't add port mapping proto=tcp extport=40301 intport=40301 interface="UPnP or NAT-PMP" err="no UPnP or NAT-PMP router discovered"
DEBUG[09-08|12:29:19] Recalculated downloader QoS values rtt=20s confidence=1.000 ttl=1m0s
INFO [09-08|12:29:22] Generating DAG in progress epoch=1 percentage=1 elapsed=44.984s
DEBUG[09-08|12:29:39] Recalculated downloader QoS values rtt=20s confidence=1.000 ttl=1m0s
INFO [09-08|12:29:48] Generating DAG in progress epoch=1 percentage=2 elapsed=1m11.554s
DEBUG[09-08|12:29:59] Recalculated downloader QoS values rtt=20s confidence=1.000 ttl=1m0s
INFO [09-08|12:30:13] Generating DAG in progress epoch=1 percentage=3 elapsed=1m36.181s
DEBUG[09-08|12:30:20] Recalculated downloader QoS values rtt=20s confidence=1.000 ttl=1m0s
INFO [09-08|12:30:34] Generating DAG in progress epoch=1 percentage=4 elapsed=1m57.705s

I never see the "Successfully sealed new block" message and alice's ether value never increases; it seems like a new "generate DAG" step just begins. I also notice that in my .ethash directory I have two files: "full-R23-0000000000000000" and "full-R23-290decd9548b62a8", with the "000..." file last modified at 12:28 (the same time that the process completed" and the "290..." file getting updated later. I then let this complete to 100 percent (it took 34 minutes this time), and see the following:

INFO [09-08|13:02:48] Generating DAG in progress epoch=1 percentage=98 elapsed=34m11.249s
DEBUG[09-08|13:03:04] Recalculated downloader QoS values rtt=20s confidence=1.000 ttl=1m0s
INFO [09-08|13:03:14] Generating DAG in progress epoch=1 percentage=99 elapsed=34m37.494s
INFO [09-08|13:03:14] Generated ethash verification cache epoch=1 elapsed=34m37.500s
DEBUG[09-08|13:03:24] Recalculated downloader QoS values rtt=20s confidence=1.000 ttl=1m0s
DEBUG[09-08|13:03:44] Recalculated downloader QoS values rtt=20s confidence=1.000 ttl=1m0s

Alice's ether value still hasn't increased. At this point I'm stumped as to what's going on. Any help to get me moving again would be greatly appreciated. Thanks!