Docker container cannot access internet, SMTP email not working

I’m trying to setup Vaultwarden on Unraid via Docker container, and I can’t send a test email.
I also noticed DNS and internet access doesn’t appear to work.

Your environment (Generated via diagnostics page)

  • Vaultwarden version: v1.29.1
  • Web-vault version: v2023.5.0
  • OS/Arch: linux/x86_64
  • Running within Docker: true (Base: Debian)
  • Environment settings overridden: true
  • Uses a reverse proxy: false
  • Internet access: false
  • Internet access via a proxy: false
  • DNS Check: false
  • Browser/Server Time Check: true
  • Server/NTP Time Check: n/a
  • Domain Configuration Check: true
  • HTTPS Check: false
  • Database type: SQLite
  • Database version: 3.41.2
  • Clients used:
  • Reverse proxy and version:
  • Other relevant information:

Config (Generated via diagnostics page)

Show Running Config

Environment settings which are overridden: SIGNUPS_ALLOWED, INVITATIONS_ALLOWED, ADMIN_TOKEN

{
  "_duo_akey": null,
  "_enable_duo": true,
  "_enable_email_2fa": false,
  "_enable_smtp": true,
  "_enable_yubico": true,
  "_icon_service_csp": "",
  "_icon_service_url": "",
  "_ip_header_enabled": true,
  "_smtp_img_src": "cid:",
  "admin_ratelimit_max_burst": 3,
  "admin_ratelimit_seconds": 300,
  "admin_session_lifetime": 20,
  "admin_token": "***",
  "allowed_iframe_ancestors": "",
  "attachments_folder": "data/attachments",
  "authenticator_disable_time_drift": false,
  "data_folder": "data",
  "database_conn_init": "",
  "database_max_conns": 10,
  "database_timeout": 30,
  "database_url": "***************",
  "db_connection_retries": 15,
  "disable_2fa_remember": false,
  "disable_admin_token": false,
  "disable_icon_download": false,
  "domain": "****://***********",
  "domain_origin": "****://***********",
  "domain_path": "",
  "domain_set": true,
  "duo_host": null,
  "duo_ikey": null,
  "duo_skey": null,
  "email_attempts_limit": 3,
  "email_expiration_time": 600,
  "email_token_size": 6,
  "emergency_access_allowed": true,
  "emergency_notification_reminder_schedule": "0 3 * * * *",
  "emergency_request_timeout_schedule": "0 7 * * * *",
  "enable_db_wal": true,
  "event_cleanup_schedule": "0 10 0 * * *",
  "events_days_retain": null,
  "extended_logging": true,
  "helo_name": null,
  "hibp_api_key": null,
  "icon_blacklist_non_global_ips": true,
  "icon_blacklist_regex": null,
  "icon_cache_folder": "data/icon_cache",
  "icon_cache_negttl": 259200,
  "icon_cache_ttl": 2592000,
  "icon_download_timeout": 10,
  "icon_redirect_code": 302,
  "icon_service": "internal",
  "incomplete_2fa_schedule": "30 * * * * *",
  "incomplete_2fa_time_limit": 3,
  "invitation_expiration_hours": 120,
  "invitation_org_name": "Vaultwarden",
  "invitations_allowed": true,
  "ip_header": "X-Real-IP",
  "job_poll_interval_ms": 30000,
  "log_file": null,
  "log_level": "Info",
  "log_timestamp_format": "%Y-%m-%d %H:%M:%S.%3f",
  "login_ratelimit_max_burst": 10,
  "login_ratelimit_seconds": 60,
  "org_attachment_limit": null,
  "org_creation_users": "",
  "org_events_enabled": false,
  "org_groups_enabled": false,
  "password_hints_allowed": true,
  "password_iterations": 600000,
  "push_enabled": false,
  "push_installation_id": "***",
  "push_installation_key": "***",
  "push_relay_uri": "https://push.bitwarden.com",
  "reload_templates": false,
  "require_device_email": false,
  "rsa_key_filename": "data/rsa_key",
  "send_purge_schedule": "0 5 * * * *",
  "sendmail_command": null,
  "sends_allowed": true,
  "sends_folder": "data/sends",
  "show_password_hint": false,
  "signups_allowed": true,
  "signups_domains_whitelist": "***********",
  "signups_verify": false,
  "signups_verify_resend_limit": 6,
  "signups_verify_resend_time": 3600,
  "smtp_accept_invalid_certs": false,
  "smtp_accept_invalid_hostnames": false,
  "smtp_auth_mechanism": "Login",
  "smtp_debug": false,
  "smtp_embed_images": true,
  "smtp_explicit_tls": null,
  "smtp_from": "**********************",
  "smtp_from_name": "Vaultwarden",
  "smtp_host": "*********************",
  "smtp_password": "***",
  "smtp_port": 587,
  "smtp_security": "starttls",
  "smtp_ssl": null,
  "smtp_timeout": 30,
  "smtp_username": "**********************",
  "templates_folder": "data/templates",
  "tmp_folder": "data/tmp",
  "trash_auto_delete_days": null,
  "trash_purge_schedule": "0 5 0 * * *",
  "use_sendmail": false,
  "use_syslog": false,
  "user_attachment_limit": null,
  "web_vault_enabled": true,
  "web_vault_folder": "web-vault/",
  "websocket_address": "0.0.0.0",
  "websocket_enabled": false,
  "websocket_port": 3012,
  "yubico_client_id": null,
  "yubico_secret_key": null,
  "yubico_server": null
}