问Docker容器中的Roundcube和Dovecot

EN

version: '3.7'
services:
    postfix:
        ...
    dovecot:
        ....
        ports:
            - "110:110"
            - "995:995"
            - "143:143"
            - "993:993"
        networks:
            - mail
        ....
    roundcube:
        image: roundcube/roundcubemail
        container_name: roundcube
        environment:
            - ROUNDCUBEMAIL_DEFAULT_HOST=dovecot
             # - ROUNDCUBEMAIL_DEFAULT_PORT=993
        networks:
            - proxy
            - mail

set $roundcube_upstream http://roundcube;
location /roundcube/ {
    rewrite ^/roundcube/(.*) /$1 break;
    proxy_http_version 1.1;
    proxy_set_header Connection "";
    proxy_set_header Host $host;
    proxy_pass $roundcube_upstream;
}

2019/01/31 09:29:25 [error] 460#460: *82483 upstream timed out (110: Connection timed out) while reading response header from upstream, client: 194.197.210.75, server: www.mydomain.be, request: "POST /roundcube/?_task=login HTTP/1.1", upstream: "http://172.18.0.9:80/?_task=login", host: "www.mydomain.be", referrer: "https://www.mydomain.be/roundcube/"

        - ROUNDCUBEMAIL_DEFAULT_HOST=ssl://dovecot
        - ROUNDCUBEMAIL_DEFAULT_PORT=993

errors: <1db522a3> IMAP Error: Login failed for me@mydomain.be from 172.18.0.8(X-Real-IP: ...,X-Forwarded-For: ...). Could not connect to ssl://dovecot:993: Unknown reason in /var/www/html/program/lib/Roundcube/rcube_imap.php on line 196 (POST /?_task=login&_action=login)172.18.0.8 - - [31/Jan/2019:13:57:37 +0100] "POST /?_task=login HTTP/1.1" 200 3089 "https://www.mydomain.be/roundcube/?_task=login" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:64.0) Gecko/20100101 Firefox/64.0"

2019-01-31T13:57:38.002653+01:00 536ff3507263 dovecot: auth: Debug: auth client connected (pid=35),
2019-01-31T13:57:38.010096+01:00 536ff3507263 dovecot: imap-login: Disconnected (no auth attempts in 0 secs): user=<>, rip=192.168.240.3, lip=192.168.240.2, TLS, session=<nVssksCAT7LAqPAD>