Dear All as there is no Exchange 2010, so I select Exchange 2013.
Exchange 2010 SP3, No Antivirus
We have Two AD Sites & One DAG "TIGER"
In HeadOffice: 2 Mailboxes & 2 HUB/CAS (10 Databases)
In DR: 1 Mailbox+Hub/CAS (All Roles in Single)
Now in test scenario we move only One DB users from HeadOffice to DR, while others are at HeadOffice.
In this situation my users successfully connected from DR site, while testing email flow
Users from DR send me email and I received in my Inbox
When I from HeadOffice send email to DR users they didnt receive any email.
I found all mails in DR Server Queues "Site=Active Directory Site" Error" 451 4.4.0 dns query failed smtpsend.dns.nonexistentdomain"
Can someone please help me to troubleshoot/resolve this issue.
Regards
Safiullah Khan