RE: Why Frontend server need TCP port 53

  • From: "Whitaker, Matthew" <Matthew.Whitaker@xxxxxxxx>
  • To: "[ExchangeList]" <exchangelist@xxxxxxxxxxxxx>
  • Date: Mon, 11 Nov 2002 06:43:27 -0700

You do not need port 53 open as long as you have an external DNS server
you can poll for look ups.

-----Original Message-----
From: ONG Liang Bu (CSC) [mailto:lbong@xxxxxxxxxx] 
Sent: Monday, November 11, 2002 6:30 AM
To: [ExchangeList]
Subject: [exchangelist] Why Frontend server need TCP port 53

Need an answer for this to the management.

For the Frontend - Backend configuration as this technet article;en-us;280132

Management is asking on TCP/UDP port 53 that needs to be open up. For
UDP 53 is the name queries so no issues, but for TCP 53, is asking for
DNS zone transfer which violate some security issue.  Anybody knew why
need TCP port 53? From the article the frontend server is not running
DNS and has to go back to the DC for DNS queries, stuck in this for the
past 2 days, any reason? anyone? Thanks, much appreciated.

Ong LB
Exchange Admin
National Institute of Education
Nanyang Technological Univeristy

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