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MX REcord change RRS feed

  • Question

  • Hi, I have a question regarding MX record. We have SBS 2011 and currently one ISP is hosting excahnge services. I would like to change that so that finally exchange can be transfered to SBS . Unfortunatelly since I am still junior admin, I am not so sure what to do. I know that change of MX record should point to FQDN.

    - Which domain name is that , the remote.domain.com or domain.com or machine.domain.com ?

    - Can I use IP address instead since we have 2 ISP and 2 internet connections ??

    - After that what am I suppose to do with Firewall/NAT regarding ports ?

    - Currently I can send e-mails from SBS 2011 that means that send connector is configured and no obstical in the network exist, but this is inbound . Do I need to open ports and NAT POP and SMTP messages ? 

    - I saw that in SBS 2011 in DNS no MX record exist , is this normal since send connector is operational ? 

    Please any help is appreciated  

    Friday, June 22, 2012 9:23 AM

Answers

  • Contact your ISPs and ask them for the FQDN, ours is like this: "host192-168-0-32.in-addr.btopenworld.com"

    You can set up both internet connections to receive, giving them different priorities eg. 5 and 10

    Firewall - If it is an external firewall, set it to allow smtp and pop (inbound and out), otherwise nothing needs doing to the Windows firewall

    In exchange console, make sure that the Accepted Domain contains your "emaildomain.com" in Hub Transport

    For us, the MX record is set in our website hosting account.

    • Proposed as answer by James - DNAerp Friday, June 22, 2012 9:55 AM
    • Marked as answer by James Xiong Thursday, June 28, 2012 12:52 AM
    Friday, June 22, 2012 9:46 AM
  • The 'FQDN' James refers to is actually his (rather odd, and indicating BT have him behind NAT) PTR record.

    Are either/both of your connections static public IP addresses?

    MX records need only exist in public DNS (where they are actually optional in some circumstances) and if you have 2 static IP connections there's a couple of ways you can handle it. If either/both are dynamic IP we handle it slightly differently.

    Also, if you wish to primarily use one or the other connection for incoming traffic, with fallback to the other connection only if primary is down, we do it one way, vs 'shared use' which would maybe do it another way.

    2 static IP's and random sharing of incoming requests is maybe the easiest.

    In public DNS (ie. not on SBS) you create _2_ A records for the same name, remote.company.com is easy. The one name points to the static IP of _both_ connections. This is a condition referred to as 'round robin DNS' and anyone requesting name resolution will be (pretty well randomly) returned one or the other IP.

    The advantage to this is that no matter which connection is down the 'name' matches the IP. Disadvantage being a lack of control about which connection is used.

    In this case _public DNS_ need only have one MX record. MX records should point to A records, and as you have only one 'name' in use MX should point to that name.

    • Proposed as answer by James Xiong Monday, June 25, 2012 1:54 AM
    • Marked as answer by James Xiong Thursday, June 28, 2012 12:52 AM
    Friday, June 22, 2012 12:31 PM

All replies

  • Contact your ISPs and ask them for the FQDN, ours is like this: "host192-168-0-32.in-addr.btopenworld.com"

    You can set up both internet connections to receive, giving them different priorities eg. 5 and 10

    Firewall - If it is an external firewall, set it to allow smtp and pop (inbound and out), otherwise nothing needs doing to the Windows firewall

    In exchange console, make sure that the Accepted Domain contains your "emaildomain.com" in Hub Transport

    For us, the MX record is set in our website hosting account.

    • Proposed as answer by James - DNAerp Friday, June 22, 2012 9:55 AM
    • Marked as answer by James Xiong Thursday, June 28, 2012 12:52 AM
    Friday, June 22, 2012 9:46 AM
  • The 'FQDN' James refers to is actually his (rather odd, and indicating BT have him behind NAT) PTR record.

    Are either/both of your connections static public IP addresses?

    MX records need only exist in public DNS (where they are actually optional in some circumstances) and if you have 2 static IP connections there's a couple of ways you can handle it. If either/both are dynamic IP we handle it slightly differently.

    Also, if you wish to primarily use one or the other connection for incoming traffic, with fallback to the other connection only if primary is down, we do it one way, vs 'shared use' which would maybe do it another way.

    2 static IP's and random sharing of incoming requests is maybe the easiest.

    In public DNS (ie. not on SBS) you create _2_ A records for the same name, remote.company.com is easy. The one name points to the static IP of _both_ connections. This is a condition referred to as 'round robin DNS' and anyone requesting name resolution will be (pretty well randomly) returned one or the other IP.

    The advantage to this is that no matter which connection is down the 'name' matches the IP. Disadvantage being a lack of control about which connection is used.

    In this case _public DNS_ need only have one MX record. MX records should point to A records, and as you have only one 'name' in use MX should point to that name.

    • Proposed as answer by James Xiong Monday, June 25, 2012 1:54 AM
    • Marked as answer by James Xiong Thursday, June 28, 2012 12:52 AM
    Friday, June 22, 2012 12:31 PM