Inbound Load Balancing for Two Mail Server


#1

Hello ,

We do plan to buy Balance 580 :

Is it able to support Inbound Load Balancing for Two Mail Server ?

mail1.ourcompany.com MX 10 on ISP1 connection
mail2.ourcompany.com Mx 20 on ISP2 Connection

Outlook Clients from Internet able to connect only via one setting : mail.ourcompany.com

Please advice how to do this .

Thank you in advance
Best Regards
Mesut


#2

Hi,

**Email server to Email Server communication: **
By default email application (servers) is designed to be able to connect multiple mail exchange servers base on MX records preference. So inbound load-balance/fail-over is depend the defined MX records for the DNS server.

MX1: ISP1 Public IP address
MX2: ISP2 Public IP address

What you need to do is make sure you have the Port forwarding or NAT mapping rules (multiple WANs) for the Inbound access and you shouldn’t have issue if ISP1 or ISP2 is down.

The only thing that you needs should be the inbound load balance or fail-over for the mail client (outlook) to mail server whereby A records is used. There are two method that you can choose for the inbound loadbalancing or fail-over methods. For more information please refer to the URL below:

Method 1 (Peplink as public DNS server for your domain):
DNS records configured within Peplink Balance

Method 2
External DNS records at an Authoritative DNS Server

Thank You


#3

Hi Sitloongs ,

Thank you very much for your prompt reply.

Could you please explain step by step if you have time :

Our Scenario is :

Primary mail server : mail1.ourcompany.com MX 10 on ISP1 connection
Backup mail server : mail2.ourcompany.com MX 10 on ISP2 connection

Both have same MX 10 Value .

mail1.ourcompany.com ip address : 86.108.108.108
mail2.ourcompany.com ip address : 213.95.95.95

Outlook Clients from Internet wish to connect only via one setting : mail.ourcompany.com

mail.ourcompany.com IN A 86.108.108.108
mail.ourcompany.com IN A 213.95.95.95

IN ISP1-DNS serving as our name server : Reverse PTR Records are also defined :

108.108.108.86.in-addr.arpa name = mail.ourcompany.com
95.95.95.213.in-addr.arpa name = mail.ourcompany.com

Please advice if our scenario can be deployed successfully .If yes how to deploy this on BALANCE 580 with demo screens

Thank you in advance
Best Regards
Mesut

DNS for ourcompany.com is hosted by ISP1


#4

Hi,

As explained, Email client to Email server communication is not related to the MX records defined. MX records is used only for Email server to Email server communication.

  • Assume you had hosted your own email server behind the Balance 580
  • Public DNS server is hosted at ISP.

Email server to Email Server communication (Outgoing/Incoming emails):

DNS records defined for ISP hosted DNS server:
Primary mail server : mail1.ourcompany.com MX 10 on ISP1 connection
Backup mail server : mail2.ourcompany.com MX 10 on ISP2 connection

Both have same MX 10 Value .

mail1.ourcompany.com ip address : 86.108.108.108
mail2.ourcompany.com ip address : 213.95.95.95

You only need to had the corresponding Port Forwarding Rules/NAT mapping rules for ISP1 & ISP2. Please refer to the details steps below for Port Forwarding Rules/NAT mapping rules.

Port Forwarding

NAT Mapping

Outlook Clients from Internet wish to connect only via one setting : mail.ourcompany.com

Seem DNS server is hosted at ISP thus you should refer to the Method2 as mention previously

External DNS records at an Authoritative DNS Server

  1. You need to request DNS vendor to delegate the mail.ourcompany.com records to Balance 580.

Current DNS records defined for ISP hosted DNS server:
mail.ourcompany.com IN A 86.108.108.108
mail.ourcompany.com IN A 213.95.95.95

Delegation:
mail NS WAN1BalanceWANIP
mail NS WAN2BalanceWANIP
WAN1BalanceWANIP WAN1_IP_Address_Balance580 <— IP address
WAN2BalanceWANIP WAN2_IP_Address_Balance580 <— IP address

  1. Make sure DNS service is enabled for B580 & Domain Name: ourcompany.com is created for mail A records

Detail steps please refer to the URL below:

If you still have difficulties to get this work, please contact Peplink local partner for assistance.

Thank You


#5

Hi Sitloongs

Thank you very much for your great support and explanations.
All is clear from now on.
We are going to order Balance 580 via your certified-partner .

Best Wishes
Mesut