I manage a server at a hosting company. apache is setup to listen on port 80 and 443. http (port 80) traffic works fine. I can also ftp and telnet fine using port 22. Issue - when I try to connect using https I get server not found. So I turned on tcptrack and I can see my https requests coming in on port 21, which is not being listened on. The domain name is assigned to a public IP which is assigned to a private IP assigned to the server. This is the third server I have setup and the other 2 are fine. Just this one RedHat server has this issue. Any help would be appreciated.

lsmod | grep ip_tables
ip_tables              55329  2 iptable_filter,iptable_mangle
x_tables               50377  3 ip_tables,ipt_REJECT,xt_tcpudp

iptables -L
Chain INPUT (policy ACCEPT)
target     prot opt source               destination

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination
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    Just to be safe, could we also get the output of iptables -t nat -L -n -v? – MadHatter Jun 13 '12 at 20:12

Have you talked to your hosting company about their NAT rules? I'm assuming they manage the NAT rules that send traffic from their public IP to your private IP


If it is coming in to the server on port 21, there is probably some port translation happening on the firewall (or whatever is on the edge). Check the same device that is translating the public to private IPs.

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