5 Replies Latest reply: Nov 12, 2012 12:53 AM by Christopher Imes RSS

Mirrorview /s  - Secondary Image Recovery Policy

james99

 

Hi

 

Could someone tell the me the pros and cons of both automatic and manual recovery policy?

 

What are the implications of using either automatic or manual recover policy in the event of a SAN failure on our remote/secondary site?

 

Thanks

 

  • 1. Re: Mirrorview /s  - Secondary Image Recovery Policy
    RRR

    If set to automatic when the line goes down and comes back up, the replication is resumed, which could be not what you want when for example a cluster failover is already in progress. On the other hand, if you're only replicating data and you're not automatically failing over servers as well resuming replication might be great for you.

  • 2. Re: Mirrorview /s  - Secondary Image Recovery Policy
    Ankit

    Recovery Policy specifies the policy for recovering the secondary mirror image after a system fracture.

    Automatic specifies that recovery automatically resumes as soon as the primary image determines that the secondary mirror image is once again accessible.

    Manual specifies that the administrator must explicitly start a synchronization operation to recover the secondary mirror image.

     

    Simply put, If access to the secondary storage image fails, the primary storage system will fracture the remote mirror. If the problem with the secondary is minor (for example, replacing a cable), then the administrator can fix it. Mirroring will recover and resynchronize the image, if the image recovery policy is Automatic. If the recovery policy is set to manual, then MirrorView/A will administratively fracture the image after the connection is restored, and an administrator must start the synchronization.

  • 3. Re: Mirrorview /s  - Secondary Image Recovery Policy
    RRR

    Your answer is more complete, but about what I said, yes.

  • 4. Re: Mirrorview /s  - Secondary Image Recovery Policy
    Ankit

    I try and post the complete and detailed answer. It not only helps the person asking the query but also helps in future queries as reference to other.

     

    Ankit

  • 5. Re: Mirrorview /s  - Secondary Image Recovery Policy
    Christopher Imes

    In addition to what was already said, I would like to mention that when the secondary is promoted, the recovery policy is set to Manual even if it was Automatic originally.  Worth noting if you were expecting it to recover from link failures automatically after you issued a promote (either to secondary and of course when promoted back to original primary).

     

    It is a question that I occassionally get months/years after having implemented MirrorView.  Even though during the implementation I'll remind them, but of course I understand, time goes by and it is forgotten.  However, it could have an impact on your RPO if you were all along relying it being Automatic.  Then again, it should go without saying that even at Automatic, it still should be occassionally reviewed.