How to configure Autodiscover for multiple EXCHANGE SERVER 2016

Question

My exchange 2016 organization is experiencing issues as described below:

Outlook client disconnects and connects randomly, OWA and ECP takes too long to load, exchange management shell breaks abruptly.

Everything was working well until DAG was set up.

Working set up:
EX201601 internal IP: 128.1.x.20

FQDN: mail.mydomain.com resolves to this public IP: 41.230.x.x

Internal DNS: In my mydomain.com zone there is two A records for the exchange server EX201601.

1. autodiscover.mydomain.com resolves to the internal IP of the exchange server
2. mail.mydomain.com resolves to the internal IP of the exchange server

All virtual directories are configured to use mail.mydomain.com both internal and external access.
Autodiscover URL is set: https://EX201601.myinternaldomain.com/autodiscover/audiscover.xml

UNWORKING SET UP
My is databases are [DB01, DB02, DB03, DB04]
IPLESS DAG is configured with four exchange server 2016 all in the same VLAN, 128.1.x.x
All four database copy in each DAG members have a status of healthy.
All databases are mounted in EX201601, [the other DAG members is: EX201602, EX201603, EX201604]

DNS:
round robin is enabled
Internal DNS inside my mydomain.com zone i have an A record entry for each of those DAG members,
mail.mydomain.com resolves to a internal IP of EX201601
mail.mydomain.com resolves to a internal IP of EX201602
mail.mydomain.com resolves to a internal IP of EX201603
mail.mydomain.com resolves to a internal IP of EX201604

Autodiscover URL is set to use their internal server FQDN.

In this DAG set up, users are experiencing the issues mentioned at the top. So to temporarily allow users to connect to outlook, ecp and owa, i just suspended database copy in each DAG members. Upon disabling everything is back to normal.

Have done a few research and figured its an issue with how autodiscover is configured, the problem is i do not know how to implement autodiscover for all DAG members such that if one member is offline the others take on the job without suspending database copy. The goal for DAG is to be on a constant replication.

What could be the issue with this autodiscover set up for my four exchange servers?

My ssl certificate has autodiscover.mydomain.com and mail.mydomain.com in it

Answer 1

Hi @Benard Mwanza ,

According to your description. OWA and ECP still works fine, right? Just need to take a long time to connect.

After you disabled the database copy, the OWA and ECP back to normal.

This issue seems to be caused by the DAG is performing database replication.

Generally, it may occur with the network. You may need to increase the Network bandwidth to solve this issue.

Here’s also two documents about load balance for you reference.
https://learn.microsoft.com/en-us/exchange/architecture/client-access/load-balancing?view=exchserver-2019#load-balancing-deployment-scenarios-in-exchange-server
https://techcommunity.microsoft.com/t5/exchange-team-blog/load-balancing-in-exchange-2016/ba-p/604048

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