Client occasionaly doesn't connect

Description

When I start Rocketchat client (version 2.17.7) client doesn’t connect to server once in 10 times (on the average). It freezes on a screen where 3 dots are showed on the gray background. Then I restart it and it connects. Or it doesn’t, in this case I restart it again and again and suddenly it connects and gives me list of channels and other things.
Thing I don’t understand: in /var/log/nginx/access.log I have only IP addresses of my own PC and my monitoring server. Where are entries for other clients? I have plenty of them in LAN and most of them are successfully connecting right now. Why don’t I see them in Nginx access log?

Server Setup Information

  • Version of Rocket.Chat Server:
    3.5.0
  • Operating System:
    Kubuntu 20.04 desktop - server
    Windows 7 - client
  • Deployment Method:
    Docker containers
  • Number of Running Instances:
    1
  • DB Replicaset Oplog:
    ?
  • NodeJS Version:
    12.16.1
  • MongoDB Version:
    4.0.19
  • Proxy:
    Nginx (don’t see it version)
  • Firewalls involved:
    ufw, all needed rules are enabled

Any additional Information

Nginx access log:
“Sorry, new user can have only 2 links in a post”
Sorry, can’t post Nginx log because of the Rocketchat forum policy.

I’ve realized that in my client I have 2 paths to server - through http and https. Https-requests go directly into access.log. But http-requests don’t. Why?
Nginx configuration was taken from this manual: https://docs.rocket.chat/installation/docker-containers#5-installing-nginx--ssl-certificate


Add output of “nginx -T && nginx -v”: https://pastebin.com/BVZKZpVi

Now I understand that it’s not Nginx who accepts requests from the client - it’s Meteor framework in Rocketchat container. So I’ve looked into Meteor’s logs:


The first log was written after client had succesfully connected, the second one when client had freezed on that screen with 3 dots.

The only difference I can see between them is that in the second log this line is missed:

API ➔ debug POST: /api/v1/method.call/loadHistory

Is it helpful information?