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phscott's avatar
phscott
Level 3
10 years ago

Has anybody used round-robin DNS for a media server?

I believe I have my environment mostly rid of the scourge of host files.  I have certain subnets with large footprint Windows Server clients that I would wish to connect a media server directly to (subnet not client).  Knowing that round-robin DNS would only connect half of the time on the subnet in question, it would still be better than traversing the entire network all of the time.  Would the host resolution in NBU be able to handle this?  What would be some of the traps you could forsee in attempting something like this?  My master is OEL (RHEL) 6.6/NBU 7.6.0.4 and my media servers are Symantec appliances running 2.6.0.4.  

 

Thank you for your input!

  • ... and netbackup with unresponsive dns is a bad place to go...it grinds to a halt with many functions.

    Might help if you can clarify how your dns is set up and why it "only connect half the time". Sounds unusual!

    Jim

  • In my experience, I root out round-robin DNS entries - I've always had a bad time with them.  It's one of the classic initial steps of debugging client -> media server connectivity is to check whether round robin DNS exists and if found get it removed.

  • Don't use any DNS that answers only half the time (normal or round robin).

    Netbackup rely heavily on DNS. its my assumption the built-in DNS cache is not supposed to recover from missing DNS respond but to lower the amount of DNS request sent. After all you never know if the "missing" DNS reply is for something new or something known - so to say. 

    Bottom line - you need perfect working DNS servers when using Netbackup.

     

6 Replies

  • No idea what 'round-robin DNS', but if you say it only works halve of the time, I don't think this is a good idea. NBU tries hostname lookup only once. If it cannot resolve, connection and backup will fail.
  • ... and netbackup with unresponsive dns is a bad place to go...it grinds to a halt with many functions.

    Might help if you can clarify how your dns is set up and why it "only connect half the time". Sounds unusual!

    Jim

  • In my experience, I root out round-robin DNS entries - I've always had a bad time with them.  It's one of the classic initial steps of debugging client -> media server connectivity is to check whether round robin DNS exists and if found get it removed.

  • Why are you using round-robin DNS inside your environment? Its used on the web for web servers etc.

  • Don't use any DNS that answers only half the time (normal or round robin).

    Netbackup rely heavily on DNS. its my assumption the built-in DNS cache is not supposed to recover from missing DNS respond but to lower the amount of DNS request sent. After all you never know if the "missing" DNS reply is for something new or something known - so to say. 

    Bottom line - you need perfect working DNS servers when using Netbackup.

     

  • Thank you for your responses.  Your responses have brought me back down to reality.  After thinking about it, I was attempting to address performance issues with unorthodox means, when the answer is to force resolution to the issue at hand.

     

    Thanks again!