JSI Tip 6967. Windows Server 2003 DNS is sending large UDP packets that your firewall can't handle?

RFC 2671 allows UDP packets greater than 512 bytes. If you firewall cannot pass these packets, Windows Server 2003 DNS does NOT fall back to TCP/IP, as was the case in previous versions of Windows NT-based operating systems.

To disable the EDNS-0 feature, eliminating the UPD packets > 512 bytes:

1. Install the Windows Server 2003 Support Tools from the CD-ROM.

2. Open a CMD prompt.

3. Type dnscmd /Config /EnableEDnsProbes 0 and press Enter.

TAGS: Windows 8
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