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Exchange 2013 SP1: Impossible to Convert IP Less DAG to IP DAG

Recently I came across with an issue where situation demanded to convert an IP Less DAG to IP DAG. I am sharing the experience so that you are aware about the technology and plan better.

We all know Exchange 2013 SP1 on Windows 2012 R2 had provided us the feature of IP Less Dag which reduced so many components of a cluster and made it a simple cluster exchange. I posted the blog of creating IP Less Dag here and also delivered a session in Tech Stravaganza Times Square New York Conference. You can watch the Video here.

In one of the environment we have IP Less DAG and for the backup we have Backup Exec. At this moment Backup Exec or net backup does not support IP Less DAG and their recommended solutions are mentioned below:


Backup Exec Solution for IP Less DAG:

NetBackup Solution for IP Less DAG:


Now Backup Exec is telling us to move to the traditional IP DAG which will create CNO and DNS entry for it.

As per my understanding Backup Exec is an application which is not a production application rather an application which just take a backup of production application and there are multiple backup application available to replace Backup Exec if they can’t go along with the technology. So I have posted my query in Symantec Forum here. I will post here if I will get any update from the Symantec forum.


Now Let us talk about converting IP Less DAG to IP DAG.

There is no way to convert an IP Less DAG to an IP DAG. Microsoft has clarified here under the topic “converting an Existing DAG”. So if you are willing to use Backup Exec which I agree has been an exchange friendly backup software from years then you need to break the current DAG then form a new cluster and add the database. I will be posting a blog on this sooner and I will add the link here.


As if now, my goal is to share the information that IP Less DAG might not be supported in your backup or other monitoring softwares because they need CNO. The work around is to add a host file entry on the backup exec server with the name of DAG and IP of any DAG member mailbox Server.



IP LESS DAG can’t be converted to Traditional DAG or visa versa. So it is better to plan ahead and check the compatibility before going for any new solution design.


Prabhat Nigam

Microsoft Solutions Architect | Exchange Server




6 Responses to “Exchange 2013 SP1: Impossible to Convert IP Less DAG to IP DAG”

  1. NeWay Technologies – Weekly Newsletter #109 – August 21, 2014 | NeWay Says:

    […] Exchange 2013 SP1: Impossible to Convert IP Less DAG to IP DAG – […]

  2. NeWay Technologies – Weekly Newsletter #109 – August 22, 2014 | NeWay Says:

    […] Exchange 2013 SP1: Impossible to Convert IP Less DAG to IP DAG – […]

  3. Sathish Says:

    Yesterday we ran into same kind of problem with one of our client who has backup Exec and this article helped us a lot to prove them that symantec doesn’t support IP Less DAG.
    Thanks a lot prabhat for the article and it saved me more time 🙂

  4. Microsoft Exchange 2013 Simplified DAG Backup – Host file to the rescue | Shane Jackson IT Pro Says:

    […] MSExchangeGURU  has a very good blog on the topic here […]

  5. Adam Says:

    Backup Exec 15 Feature Pack 2 now supports IP-less DAG for backup for those interested and referencing this article.

  6. Prabhat Nigam Says:

    Glad to hear this Adam.
    Do you have any link to share this update? I will be glad to link it.

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