NAT to Windows Cluster



  • I am setting up our new pfsense firewalls, and using NAT for our email server works great. The problem comes when I try to NAT to our Windows Server Cluster IP (ex. 10.0.0.50). I spun up a test VM and installed IIS and pointed the NAT Rule to that, and http and everything worked great. Pointed it back to the cluster IP and i always get "Connection Time out".

    I read that Window does some weird stuff and in order to get the Windows NLB (multicast) working on the pfSense, need to add the tunable : net.link.ether.inet.allow_multicast Value 1

    I added this and rebooted the pfsense, and still nothing. I am at an impasse, because the very basic firewall/router we have running now has the same basic rule that anything coming in port 80 or 443 to go to 10.0.0.50 works, but the powerful beast of pfsense does not.

    Any help is greatly appreciated.

    Also to answer the basic question, yes it is showing up on the ARP table. When I ping the Cluster from pfsense I receive Duplicate responses from all the servers. When I ping from a Windows or Linux (Mint) box I do not get any "duplicate" responses, if that makes any sense…



  • I forgot to mention, when I point it to each server directly instead of the cluster (say 10.0.0.51 or 10.0.0.52), it still does not work


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