There have 2 AD sites in 2 different locations, each with own mailbox and cas server. We have split dns implemented. Site A is internet facing and there is TMG that publishes owa externally (https://owa.ourdomain/owa).
We want that users in all sites use the same owa site internally: https://mail.ourdomain/owa
We have configured URls in the following way:
CASSite A:
InternalURL: https://mail.ourdomain/owa
ExternalURL: https://owa.ourdomain/owa
CAS Site B:
InternalURL: https://mail.ourdomain/owa
ExternalURL: $null
There are 2 mail.ourdomain A records and are both directing for CAS in Site A and Site B. There is netmask ordering configured on DNS servers, so mail.ourdomain is resolved to CAS A in Site A, and CAS B in Site B.
From Site A accessing mailboxes on both sites works correctly. From Site B accessing mailboxes located on mbx server in site B is OK, but accessing mailbox in Site A is impossible (use the following link for best performance: https://owa.ourdomain/owa). I understand that is because of ExternalURL is configured in Site B.
1. Is there a way to get proxying working instead of redirecting?
2. i tried adding a record owa.ourdomain to internal dns to point to cas in site A, but this workaround is not working (i think i should mess with iis bindings) - but will this config be supported?
Any ideas how to fix this this setup?