global
        log /dev/log    local0
        log /dev/log    local1 notice
        chroot /var/lib/haproxy
        stats socket /run/haproxy/admin.sock mode 660 level admin
        stats timeout 30s
        user haproxy
        group haproxy
        maxconn 2000
        daemon

        tune.ssl.default-dh-param 2048

        # Default SSL material locations
        ca-base /etc/ssl/certs
        crt-base /etc/ssl/private

        # Default ciphers to use on SSL-enabled listening sockets.
        # For more information, see ciphers(1SSL). This list is from:
        #  https://hynek.me/articles/hardening-your-web-servers-ssl-ciphers/
        ssl-default-bind-ciphers ECDH+AESGCM:DH+AESGCM:ECDH+AES256:DH+AES256:ECDH+AES128:DH+AES:ECDH+3DES:DH+3DES:RSA+AESGCM:RSA+AES:RSA+3DES:!aNULL:!MD5:!DSS
        ssl-default-bind-options no-sslv3

defaults
        log     global
        mode    http
        option  httplog
        option  dontlognull
        option http-no-delay
        option contstats
        option httplog
        option logasap
        log global
        # Logging Setting. Local to Local Syslog and Control from There
        log-tag haproxy

        balance source
        timeout connect 5000
        timeout client  50000
        timeout server  50000
        timeout queue 30s
        errorfile 400 /etc/haproxy/errors/400.http
        errorfile 403 /etc/haproxy/errors/403.http
        errorfile 408 /etc/haproxy/errors/408.http
        errorfile 500 /etc/haproxy/errors/500.http
        errorfile 502 /etc/haproxy/errors/502.http
        errorfile 503 /etc/haproxy/errors/503.http
        errorfile 504 /etc/haproxy/errors/504.http
        default-server inter 10s fall 3 rise 2


frontend ft_ex01
        mode http
        maxconn 2000
		## External IP or DMZ IP of Proxy Server
        bind 99.99.99.99:443 ssl crt /etc/letsencrypt/live/exchange.external.company.com/haproxy.pem ciphers ECDHE+aRSA+AES256+GCM+SHA384:ECDHE+aRSA+AES128+GCM+SHA256:ECDHE+aRSA+AES256+SHA384:ECDHE+aRSA+AES128+SHA256:ECDHE+aRSA+AES256+SHA:ECDHE+aRSA+AES128+SHA:AES256+GCM+SHA384:AES128+GCM+SHA256:AES128+SHA256:AES256+SHA256:DHE+aRSA+AES128+SHA:HIGH:!aNULL:!eNULL:!LOW:!3DES:!MD5:!EXP:!PSK:!SRP:!DSS
        # Define a List of Accepted ACLs for Future use
        acl all-exchange path_beg -i /autodiscover /owa /oab /ews /public /microsoft-server-activesync /rpc /ecp /mapi /favicon.ico
        acl root url_len 1
        acl mail_internal_dns hdr(host) -i exchange.internal.company.com

        http-request deny unless all-exchange OR root OR mail_internal_dns
        http-request redirect code 301 location https://exchange.external.company.com if mail_internal_dns

        # Redirect is the URL is a Single Character, which can only mean /
        #redirect location /owa if root
        # Capture the User-Agent Header, so that it is Added to the Log
        capture request header User-Agent len 50
        capture request header Content-Length len 120
        capture response header Content-Length len 120
        default_backend bk_exchange


frontend ft_http
        mode http
        maxconn 2000
        bind 99.99.99.99:80    ## External IP or DMZ IP of Proxy Server
        acl letsencrypt path_beg -i /.well-known

        acl mailbt_dns hdr(host) -i exchange.external.company.com

        acl root url_len 1
        http-request deny unless letsencrypt OR mail_dns
        capture request header User-Agent len 50
        capture request header Content-Length len 120
        capture response header Content-Length len 120

        http-request redirect code 301 location https://exchange.external.company.com if mail_dns !letsencrypt
        default_backend localh

backend bk_exchange change
        mode http
        fullconn 500
		## internal connection to exchange server
        server exchange.internal.company.com 192.168.0.10:443 check ssl verify none

backend localh
        mode http
        fullconn 500
        server localhost 127.0.0.1:8081     ## Serving let's encrypt well-known. (http)