none
Office 365 Hybrid Exchange server port requirements RRS feed

  • Question

  • I want to have answers in simple words for below queries:

    1. Will port 25 and 443 need to be opened BOTH WAYS from Hybrid Exchange servers to Exchange online? Or one way?

    2. Will IMAP, POP3, SMTP relay (587) port need to be opened from the entire internal network one way? Or both way to and from Hybrid exchange servers.

    I have gone through the microsoft article, it is not clear about the source, destination and if need to be opened both way or one way. Please help.


    Regards BM

    Thursday, November 14, 2019 10:14 AM

Answers

  • I want to have answers in simple words for below queries:

    1. Will port 25 and 443 need to be opened BOTH WAYS from Hybrid Exchange servers to Exchange online? Or one way?

    2. Will IMAP, POP3, SMTP relay (587) port need to be opened from the entire internal network one way? Or both way to and from Hybrid exchange servers.

    I have gone through the microsoft article, it is not clear about the source, destination and if need to be opened both way or one way. Please help.


    Regards BM

    1. Yes, both ways.

    2. NO, Hybrid doesnt use  IMAP or POP or 587. Thats a client thing.


    Thursday, November 14, 2019 11:18 AM
    Moderator
  • Hi,

    Here is an information about Hybrid deployment protocols, ports, and endpoints, 443 and 25 port are needed.Those two ports are used for communicate with Office 365 and Exchange on-premises, so this is two-way.

    Regards,

    Kyle Xu


    Please remember to mark the replies as answers if they helped. If you have feedback for TechNet Subscriber Support, contact tnsf@microsoft.com.

    • Marked as answer by GoodResource Saturday, November 16, 2019 7:32 AM
    Friday, November 15, 2019 9:01 AM
    Moderator

All replies

  • Hello,

    1/Port 443 both way (you can reduce the ip source for this port , cf O365 ip ranges )

    Port 25 (i suppose your server can go out with port 25 and receive too)

    for port 25, this is used by internal:

    - relay from onprem to O365

    - user still on Onprem to send mail to O365 with correct send connector

    2/ if you are using these service, try to manage them with the local onprem server (this one need to stay onprem to manage your O365 object) but :

    imap, can be use. (if application need it)

    pop3 can be use.(if application need it)

    port 587(use the - flux mail-  connector from O365 dashboard to relay from onprem to O365)

    Olivier.





    Thursday, November 14, 2019 10:39 AM
  • I want to have answers in simple words for below queries:

    1. Will port 25 and 443 need to be opened BOTH WAYS from Hybrid Exchange servers to Exchange online? Or one way?

    2. Will IMAP, POP3, SMTP relay (587) port need to be opened from the entire internal network one way? Or both way to and from Hybrid exchange servers.

    I have gone through the microsoft article, it is not clear about the source, destination and if need to be opened both way or one way. Please help.


    Regards BM

    1. Yes, both ways.

    2. NO, Hybrid doesnt use  IMAP or POP or 587. Thats a client thing.


    Thursday, November 14, 2019 11:18 AM
    Moderator
  • Hi,

    Here is an information about Hybrid deployment protocols, ports, and endpoints, 443 and 25 port are needed.Those two ports are used for communicate with Office 365 and Exchange on-premises, so this is two-way.

    Regards,

    Kyle Xu


    Please remember to mark the replies as answers if they helped. If you have feedback for TechNet Subscriber Support, contact tnsf@microsoft.com.

    • Marked as answer by GoodResource Saturday, November 16, 2019 7:32 AM
    Friday, November 15, 2019 9:01 AM
    Moderator
  • I am still not clear on this. If you can help please. i am not sure why i find it so difficult to understand O365 URL and IP ranges website nowadays.

    1. From Hybrid to O365, port 25 and 443 need to be open bidirectional. Is it true? or do i need to open from any internet network to Hybrid and vice versa? Please confirm.

    2. From internal network our security only approving 80 and 443. SMTP and IMAP and others will be done case by case basis.

    Please let me know if it is okay?


    Regards BM

    Wednesday, November 20, 2019 6:59 AM
  • Hi,

    Here is a summary for this thread which my be useful to you:

    Question:

    What record need for hybrid Exchange with Office 365.

    Solution Summary:

    25 and 443 port are needed. About IMAP and POP, it is connect to target server(Outgoing and Incoming) directly, they don't  related with hybrid or not.

    Regards,

    Kyle Xu


    Please remember to mark the replies as answers if they helped. If you have feedback for TechNet Subscriber Support, contact tnsf@microsoft.com.

    Sunday, November 24, 2019 11:56 AM
    Moderator