Failed to open TCP connection エラーの解決方法について

前提・実現したいこと

Docker上のredmineのチケット作成の通知をmattemostに飛ばそうとしています。

まず、Windows10のHyper-VにCentOSを導入し、
その上にDockerを導入、RedmineとMattermostを構築しています。

以下を参考にredmine_messengerプラグインを導入、環境設定を行いました。
リンク

しかし、redmineでチケットを作成してもmattermostに通知が行きません。
redmineをのログ(詳細は下部)を確認すると、以下のエラーが出力されていました。

cannot connect to http://100.64.1.30:8065/hooks/tj9p7fkhcp8aichbink1odehoc
Failed to open TCP connection to 100.64.1.30:8065 (No route to host - connect(2) for "100.64.1.30" port 8065)

有識者の方々、解決方法のご教示お願いいたします。

環境

ホストOS

# cat /etc/redhat-release
CentOS Linux release 7.6.1810 (Core)
# docker -v
Docker version 18.09.0, build 4d60db4
# docker-compose -v
docker-compose version 1.18.0, build 8dd22a9

コンテナ

[root@localhost ~]# docker ps
CONTAINER ID        IMAGE                               COMMAND                  CREATED             STATUS              PORTS                                                          NAMES
61aef70d47d3        mattermost/mattermost-preview:5.0   "/bin/sh -c ./docker…"   15 minutes ago      Up 13 minutes       3306/tcp, 33060/tcp, 0.0.0.0:8065->8065/tcp                    mattermost
f989968b6778        bitnami/nginx                       "/entrypoint.sh /run…"   26 hours ago        Up About an hour    0.0.0.0:80->80/tcp, 8080/tcp, 0.0.0.0:443->443/tcp, 8443/tcp   redmine_nginx
8a56e6af6f32        sameersbn/redmine:3.4.2             "/sbin/entrypoint.sh…"   26 hours ago        Up About an hour    0.0.0.0:10083->80/tcp, 0.0.0.0:10443->443/tcp                  redmine
447844f60cf6        sameersbn/mysql:latest              "/sbin/entrypoint.sh…"   26 hours ago        Up About an hour    3306/tcp                                                       redmine_mysql
cf69f887748f        sameersbn/memcached:latest          "/sbin/entrypoint.sh…"   26 hours ago        Up About an hour    11211/udp, 0.0.0.0:11211->11211/tcp                            redmine_memcached

docker-compose.yml

version: '3.3'

services:
  memcached:
    image: 'sameersbn/memcached:latest'
    container_name: redmine_memcached
    ports:
      - '11211:11211'
    restart: always
  mysql:
    image: 'sameersbn/mysql:latest'
    container_name: redmine_mysql
    environment:
      - DB_USER=bn_redmine
      - DB_PASS=password
      - DB_NAME=redmine
    volumes:
      - /srv/docker/redmine/mysql:/var/lib/mysql
  redmine:
    image: 'sameersbn/redmine:3.4.2'
    container_name: redmine
    depends_on:
      - mysql
      - memcached
    ports:
      - "10083:80"
      - "10443:443"
    volumes:
      - /srv/docker/redmine/redmine:/home/redmine/data
    environment:
      - TZ=Asia/Tokyo
      # DBの設定
      - DB_ADAPTER=mysql2
      - DB_HOST=mysql
      - DB_PORT=3306
      # redmineの設定
      - DB_USER=bn_redmine
      - DB_PASS=password
      - DB_NAME=redmine
      # redmine http設定
      - REDMINE_PORT=10083
      - REDMINE_HTTPS=false
      - REDMINE_CONCURRENT_UPLOADS=2
  lb:
    image: 'bitnami/nginx'
    container_name: redmine_nginx
    depends_on:
      - redmine
    volumes:
      - /opt/bitnami/nginx_data:/bitnami/nginx
    ports:
      - 80:80
      - 443:443

発生している問題・エラーメッセージ(redmineログ)

※IPは適当な値に書き換えています。

Started POST "/projects/test/issues" for 100.64.1.47 at 2019-09-28 01:45:57 +0900
Processing by IssuesController#create as HTML
  Parameters: {"utf8"=>"?", "authenticity_token"=>"HAX4lSp+2S7HaF8sV8jnu8jfjW0mm+tc/m2OGFEk4yrcaqQq8TMSTfRtFu/zgvgk4AWXHEQGoAxCwI2WuAqrBQ==", "form_update_triggered_by"=>"", "issue"=>{"is_private"=>"0", "tracker_id"=>"1", "subject"=>"aa", "description"=>"", "status_id"=>"1", "priority_id"=>"2", "assigned_to_id"=>"", "parent_issue_id"=>"", "start_date"=>"2019-09-28", "due_date"=>"", "estimated_hours"=>"", "done_ratio"=>"0"}, "issue_template"=>"", "template_search_filter"=>"", "was_default_status"=>"1", "commit"=>"作成", "project_id"=>"test"}
  Current user: admin (id=1)
  Rendered mailer/_issue.text.erb (2.6ms)
  Rendered mailer/issue_add.text.erb within layouts/mailer (3.3ms)
  Rendered mailer/_issue.html.erb (2.2ms)
  Rendered mailer/issue_add.html.erb within layouts/mailer (2.9ms)
cannot connect to http://100.64.1.30:8065/hooks/tj9p7fkhcp8aichbink1odehoc
Failed to open TCP connection to 100.64.1.30:8065 (No route to host - connect(2) for "100.64.1.30" port 8065)
Redirected to http://100.64.1.30:10083/issues/5
Completed 302 Found in 1160ms (ActiveRecord: 52.9ms)
Started GET "/issues/5" for 100.64.1.47 at 2019-09-28 01:45:58 +0900
Processing by IssuesController#show as HTML
  Parameters: {"id"=>"5"}
  Current user: admin (id=1)
  Rendered issues/_action_menu.html.erb (5.9ms)
  Rendered issue_relations/_form.html.erb (4.0ms)
  Rendered issues/_relations.html.erb (5.0ms)
  Rendered issues/_action_menu.html.erb (4.1ms)
  Rendered issues/_form_custom_fields.html.erb (0.1ms)
  Rendered issues/_attributes.html.erb (13.9ms)
  Rendered issues/_form.html.erb (29.9ms)
  Rendered attachments/_form.html.erb (2.8ms)
  Rendered issues/_edit.html.erb (50.5ms)
  Rendered issues/show.html.erb within layouts/base (118.8ms)
Completed 200 OK in 228ms (Views: 141.5ms | ActiveRecord: 55.0ms)```

試したこと

切り分けになっているかわかりませんが、
curlコマンドでホストOSからコンテナに疎通を確認したところ、
redmine(10083)は通りますが、mattermost(8065)には通りませんでした。

# curl --verbose telnet://100.64.1.30:10083
* About to connect() to 100.64.1.30 port 10083 (#0)
*   Trying 100.64.1.30...
* Connected to 100.64.1.30 (100.64.1.30) port 10083 (#0)

#
#
# curl --verbose telnet://100.64.1.30:8065
* About to connect() to 100.64.1.30 port 8065 (#0)
*   Trying 100.64.1.30...
* Connected to 100.64.1.30 (100.64.1.30) port 8065 (#0)

HTTP/1.1 400 Bad Request
Content-Type: text/plain; charset=utf-8
Connection: close