Facility wide DR/Continuity

Bill Woodcock woody at pch.net
Wed Jun 3 17:47:13 UTC 2009

      On Wed, 3 Jun 2009, Drew Weaver wrote:
    > Should the additional sites be connected to the primary site 
    > (and/or the Internet directly)?

Yes, because any out-of-band synchronization method between the servers at 
the production site and the servers at the DR site is likely to be more 
difficult to manage.  You could do UUCP over a serial line, but...

    > What is the best way to handle the routing? Obviously two devices 
    > cannot occupy the same IP address at the same time, so how do you 
    > provide that instant 'cut-over'?

This is one of the only instances in which I like NATs.  Set up a NAT 
between the two sites to do static 1-to-1 mapping of each site into a 
different range for the other, so that the DR servers have the same IP 
addresses as their production masters, but have a different IP address to 
synchronize with.  


More information about the NANOG mailing list