I am using Digital Ocean VPS. As we play with plugin, one thing or other gets broken. Is there any way/command to take full backup of NodeBB which can be restored ?
Take a snapshot using your digital ocean account, switch it off in your dashboard, then snapshot. Alternatively, all plugins can be removed, even if it breaks your site. The snapshot is only valid on that droplet, so if you destroy it your snapshot goes with it.
Not really -- as mentioned prior, the reason this is impossible is because the redis database doesn't usually live in a place that is readable by NodeBB.
I already re-installed onto a new server. I was only testing .. If I do reproduce I will make sure to provide stacktrace. I do appreciate you looking into this. I will make sure in the future that I can provide more details.
If your site contains a lot of user data such as images you may want to consider using a plugin that would offload that content to a 3rd party provider such as Imgur or Amazon S3. Plugins exist for NodeBB for both of those services.
