BizTalk URI DNS change RRS feed

  • Question

  • Does BizTalk (version 2009 and 2013) require a host instance restart when the DNS record (used in the URI)  is updated to a new IP address ?  In other works, does the host instance cache the IP address resolution of the of the DNS entry for the URI? 

    One of my interfacing systems is failed over monthly.  The related DNS a record is updated with a different IP address and the BizTalk Server operating systems reflect this change within minutes.   And I'd prefer to not have to cycle through and restart host instances if I don't have to.



    Thursday, October 5, 2017 3:28 PM

All replies

  • If any manual intervention is necessary, it wouldn't be BizTalk itself that requires it.

    The entire IP stack, including DNS, is managed by Windows so your issues would be with the cache refresh in the Windows network stack.  You can force this with ipconfig /flushdns.

    However, DNS entries have a TTL (time to live) which Windows respects so Windows itself will not refresh an address mapping until the TTL expires.

    Meaning, the correct way to handle this is to shorten the TTL of the entry to some interval within your failover window.

    BizTalk Server should be unaware and uninterested in the change.  But you should test to be sure.

    Thursday, October 5, 2017 5:02 PM
  • The BizTalk Host Instance would not cache anything. The OS however does for the duration specified as TTL.

    Instead of restarting the host instance if you execute a ipconfig /flushdns command, the next invocation of the send point would force a fresh DNS resolution and if the DNS change has been propagated then the call will be sent to the specified endpoint. You can use the nslookup commands before flushing the DNS, as this queries against the DNS server, you'd know if the change has been replicated or not.


    Friday, October 6, 2017 10:07 AM