I spent a year debugging one system, added watchdog, and when watchdog was installed it restarted the system when i t didn’t need to… but there was a few moments of contact lost between front and back end, always recoverable, but watchdog killed the system… every night 4-5 times…

never did figure it out…

In the pm2 logs:

[2020-05-04 03:03:04.470] [ERROR]  Mon May 04 2020 03:03:00 GMT-0900 (Hawaii-Aleutian Daylight Time) - WatchDog: Heartbeat timeout. Frontend might have crashed. Exit now.
events.js:177
      throw er; // Unhandled 'error' event
      ^

Error [ERR_STREAM_DESTROYED]: Cannot call write after a stream was destroyed
    at doWrite (_stream_writable.js:413:19)
    at writeOrBuffer (_stream_writable.js:401:5)
    at Socket.Writable.write (_stream_writable.js:301:11)
    at Object.con.<computed> [as error] (/home/pi/MagicMirror/node_modules/console-stamp/main.js:148:46)
    at process.<anonymous> (/home/pi/MagicMirror/js/app.js:40:10)
    at process.emit (events.js:205:15)
    at process._fatalException (internal/process/execution.js:146:25)
npm ERR! code ELIFECYCLE
npm ERR! errno 7
npm ERR! magicmirror@2.11.0 start: `DISPLAY="${DISPLAY:=:0}" ./node_modules/.bin/electron js/electron.js`
npm ERR! Exit status 7
npm ERR! 
npm ERR! Failed at the magicmirror@2.11.0 start script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     /home/pi/.npm/_logs/2020-05-04T12_17_10_505Z-debug.log

Here is the npm error log

0 info it worked if it ends with ok
1 verbose cli [ '/usr/bin/node', '/usr/local/bin/npm', 'start' ]
2 info using npm@6.14.4
3 info using node@v10.19.0
4 verbose run-script [ 'prestart', 'start', 'poststart' ]
5 info lifecycle magicmirror@2.11.0~prestart: magicmirror@2.11.0
6 info lifecycle magicmirror@2.11.0~start: magicmirror@2.11.0
7 verbose lifecycle magicmirror@2.11.0~start: unsafe-perm in lifecycle true
8 verbose lifecycle magicmirror@2.11.0~start: PATH: /usr/local/lib/node_modules/npm/node_modules/npm-lifecycle/node-gyp-bin:/home/pi/MagicMirror/node_modules/.bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/local/games:/usr/games
9 verbose lifecycle magicmirror@2.11.0~start: CWD: /home/pi/MagicMirror
10 silly lifecycle magicmirror@2.11.0~start: Args: [ '-c',
10 silly lifecycle   'DISPLAY="${DISPLAY:=:0}" ./node_modules/.bin/electron js/electron.js' ]
11 silly lifecycle magicmirror@2.11.0~start: Returned: code: 1  signal: null
12 info lifecycle magicmirror@2.11.0~start: Failed to exec start script
13 verbose stack Error: magicmirror@2.11.0 start: `DISPLAY="${DISPLAY:=:0}" ./node_modules/.bin/electron js/electron.js`
13 verbose stack Exit status 1
13 verbose stack     at EventEmitter.<anonymous> (/usr/local/lib/node_modules/npm/node_modules/npm-lifecycle/index.js:332:16)
13 verbose stack     at EventEmitter.emit (events.js:198:13)
13 verbose stack     at ChildProcess.<anonymous> (/usr/local/lib/node_modules/npm/node_modules/npm-lifecycle/lib/spawn.js:55:14)
13 verbose stack     at ChildProcess.emit (events.js:198:13)
13 verbose stack     at maybeClose (internal/child_process.js:982:16)
13 verbose stack     at Process.ChildProcess._handle.onexit (internal/child_process.js:259:5)
14 verbose pkgid magicmirror@2.11.0
15 verbose cwd /home/pi/MagicMirror
16 verbose Linux 4.19.97-v7+
17 verbose argv "/usr/bin/node" "/usr/local/bin/npm" "start"
18 verbose node v10.19.0
19 verbose npm  v6.14.4
20 error code ELIFECYCLE
21 error errno 1
22 error magicmirror@2.11.0 start: `DISPLAY="${DISPLAY:=:0}" ./node_modules/.bin/electron js/electron.js`
22 error Exit status 1
23 error Failed at the magicmirror@2.11.0 start script.
23 error This is probably not a problem with npm. There is likely additional logging output above.
24 verbose exit [ 1, true ]

I don’t see a DM

Sending them you via DM. Stay safe!

code: ‘EAI_AGAIN’,

there was a network problem, probably outside your house… it should recover

TypeError: Cannot read property ‘parent’ of undefined
MMM-Comics

this module had an error getting data, and did not handle the error… it most likely WON’T recover by itself
why it had trouble I cannot tell

on the MM shutdown? , I would need to see the pm2 logs, --lines=100 (or more)