Alexander Dalloz wrote: > Am 15.10.2018 um 00:33 schrieb Ken Smith: >> If I telnet to port 53 from outside my LAN I get a connection. If I >> stop bind that connection is refused, confirming the local bind >> instance is getting the connection. > > You cannot test bind operating on port 53 by UDP through telnet. > > Alexander > Thank you Alexander, that's exactly right. The problem was nothing to do with the MBoard change. Investigating with dig traced the issue. Somehow the UDP port forward setting in my firewall had become corrupt. Re-establishing that fixed the issue. Not a Centos or Bind9 issue at all. Ken -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.