@alphagao link me whatever guide you're using. If you don't know what to do, use this guide:

This guide is designed for those with no knowledge in servers management in CLI (command line interface), all the installation described here can be carried out in the DSM interface from Synology.
For larger installations a Dedicated Server / VPS or hosting services like NodeBB Instant Hosting is probably preferable but for a small community or for testing purposes, this solution is functional.
Prerequisites:
A static IP address from your ISP or a Dynamic DNS configured from the NAS. (I would not detail this part, I consider that you already have it)
A Domain name that redirects to your NAS. (From Synology DDNS, GoDaddy, Bluehost, OVH, etc...)
Ports 80/443 open in your router and that redirect to your NAS
A compatible Synology NAS with DSM 6.2.x or later (see list below)
Applied Models:
20 series: FS6400, FS3400, RS820RP+, RS820+, DS620slim, SA3600, SA3400, SA3200D
19 series: RS1619xs+, RS1219+, DS2419+, DS1819+, DS1019+, DVA3219
18 series: FS1018, RS3618xs, RS2818RP+, RS2418RP+, RS2418+, RS818RP+, RS818+, DS3018xs, DS1618+, DS918+, DS718+, DS218+
17 series: FS3017, FS2017, RS18017xs+, RS4017xs+, RS3617xs+, RS3617RPxs, RS3617xs, DS3617xs, DS1817+, DS1517+
16 series: RS18016xs+, RS2416RP+, RS2416+, DS916+, DS716+, DS716+II, DS216+, DS216+II
15 series: RS815RP+, RS815+, RC18015xs+, DS3615xs, DS2415+, DS1815+, DS1515+, DS415+
14 series: RS3614xs+, RS3614RPxs, RS3614xs, RS2414RP+, RS2414+, RS814RP+, RS814+
13 series: RS10613xs+, RS3413xs+, DS2413+, DS1813+, DS1513+, DS713+
12 series: RS3412RPxs, RS3412xs, RS2212RP+, RS2212+, RS812RP+, RS812+, DS3612xs, DS1812+, DS1512+, DS712+, DS412+
11 series: RS3411RPxs, RS3411xs, RS2211RP+, RS2211+, DS3611xs, DS2411+, DS1511+, DS411+, DS411+II
*10 series: RS810RP+, RS810+, DS1010+, DS710+
(We choose a redis database here given that we want to set up a fast small forum)
Configure NodeBB installer on http://your-nas-ip:4567 in your favorite browser (your-nas-ip should be the same from Synology DSM access. Something like 192.168.X.X)
Note that in "Web address" you must indicate the external url of your forum with your own domain name with HTTPS. I don't detail in this tutorial how to buy a domain name, but if you only want to use nodebb locally, just leave the default url.
Fill in your login details for the administrator.
Fill in the information for the database as shown below
Click Install
Datas in Docker containers are not persistent by default. However, it is essential for a forum to have control over the data and be able to perform backups and restores. This is why Docker allows us to mount volumes to associate a folder on your NAS with folders inside the containers.
Note: You have to identify the absolute path of your folder depending on your volumes on your NAS. In File Station, Right click on the folder > Properties > Location. For me, it's starting with /volume1.
docker cp nodebb-docker:/usr/src/app/public/uploads /volume1/docker/nodebb
docker cp redis-nodebb:/bitnami/redis/data /volume1/docker/nodebb
if you've named your containers differently than I have, you have to change: nodebb-docker:/ and redis-nodebb:/ according to yours.
Your forum should already be operational at this stage, but we now want to be able to access it from the outside (internet) with a domain name and an SSL certificate
(the green padlock in the address bar of your browser).
@Per0x Not personally a fan of Docker but way cool that you posted this up for the benefit of others. Good on 'ya!
really nice documentation you did here
Very extensive, thanks!
@ᴅᴀʀᴛʜ-ᴠᴀᴅᴇʀ Hello, normally it is enough to stop and clear the container (not delete) with the function provided in synology, to re-download the new image in the registry and to restart the container again. You will also need to add a persistent volume to map the /usr/src/app/config.json file
Problems occur if you have installed plugins or themes. The docker image provided by nodebb is not really docker friendly so it will be possible, but more complicated.
@per0x said in Guide to install NodeBB on Docker with Synology NAS (DSM):
/usr/src/app/config.json
I make it and my Board is crahed
Can you help me?
Sorry for my english, i speak German
2021-06-12 19:44:35 stdout [cluster] Child Process (37) has exited (code: 0, signal: null)
2021-06-12 19:44:35 stdout at parseType (/usr/src/app/node_modules/redis-parser/lib/parser.js:302:14)
2021-06-12 19:44:35 stdout at parseError (/usr/src/app/node_modules/redis-parser/lib/parser.js:179:12)
2021-06-12 19:44:35 stdout 2021-06-12T19:44:35.326Z [4567/37] - [31merror[39m: ReplyError: MISCONF Redis is configured to save RDB snapshots, but it is currently not able to persist on disk. Commands that may modify the data set are disabled, because this instance is configured to report errors during writes if RDB snapshotting fails (stop-writes-on-bgsave-error option). Please check the Redis logs for details about the RDB error.
2021-06-12 19:44:35 stdout 2021-06-12T19:44:35.293Z [4567/37] - [32minfo[39m: [socket.io] Restricting access to origin: https://board.myteamspeak.online:*
2021-06-12 19:44:34 stdout 2021-06-12T19:44:34.559Z [4567/37] - [33mwarn[39m: [upgrade/appendPluginScripts] Unable to read plugin.json for plugin `nodebb-plugin-teamspeak-verify`. Skipping.
2021-06-12 19:44:34 stdout 2021-06-12T19:44:34.558Z [4567/37] - [33mwarn[39m: [upgrade/appendPluginScripts] Unable to read plugin.json for plugin `nodebb-widget-search-bar`. Skipping.
2021-06-12 19:44:34 stdout 2021-06-12T19:44:34.557Z [4567/37] - [33mwarn[39m: [upgrade/appendPluginScripts] Unable to read plugin.json for plugin `nodebb-theme-oxide`. Skipping.
2021-06-12 19:44:34 stdout 2021-06-12T19:44:34.556Z [4567/37] - [33mwarn[39m: [upgrade/appendPluginScripts] Unable to read plugin.json for plugin `nodebb-plugin-teamspeak`. Skipping.
2021-06-12 19:44:34 stdout 2021-06-12T19:44:34.555Z [4567/37] - [33mwarn[39m: [upgrade/appendPluginScripts] Unable to read plugin.json for plugin `nodebb-plugin-jwt-oauth2`. Skipping.
2021-06-12 19:44:34 stdout 2021-06-12T19:44:34.554Z [4567/37] - [33mwarn[39m: [upgrade/appendPluginScripts] Unable to read plugin.json for plugin `nodebb-plugin-sso-jwt`. Skipping.
2021-06-12 19:44:34 stdout 2021-06-12T19:44:34.553Z [4567/37] - [33mwarn[39m: [upgrade/appendPluginScripts] Unable to read plugin.json for plugin `nodebb-plugin-session-sharing`. Skipping.
2021-06-12 19:44:34 stdout 2021-06-12T19:44:34.380Z [4567/37] - [33mwarn[39m: [cache-buster] could not read cache buster ENOENT: no such file or directory, open '/usr/src/app/build/cache-buster' {"errno":-2,"code":"ENOENT","syscall":"open","path":"/usr/src/app/build/cache-buster","stack":"Error: ENOENT: no such file or directory, open '/usr/src/app/build/cache-buster'"}
2021-06-12 19:44:31 stdout 2021-06-12T19:44:31.080Z [4567/37] - [32minfo[39m: Initializing NodeBB v1.17.1 https://board.myteamspeak.online
@ᴅᴀʀᴛʜ-ᴠᴀᴅᴇʀ It probably crashes because of the plugins you installed and nodebb can't find them (nodebb-theme-oxide in particular)
I suggest you backup the redis database by copying the /data folder somewhere, then delete the contents of the original folder and also remove the config.json volume.
Erase and restart redis and nodebb container (It should be like a fresh install) then installs the plugins and themes listed in the log file (nodebb-plugin-teamspeak-verify, nodebb-widget-search-bar, nodebb-theme-oxide, etc)
When all plugins are installed and enabled, stop the nodebb container and restore the /data redis database with your backup, and remap config.json volume and I think it should be up.
Next time you want to upgrade, disable all plugins before restarting the container with the new image.