ubuntu:iptables:share_an_ip_address_between_servers
Differences
This shows you the differences between two versions of the page.
| Next revision | Previous revision | ||
| ubuntu:iptables:share_an_ip_address_between_servers [2019/11/29 17:47] – created peter | ubuntu:iptables:share_an_ip_address_between_servers [2020/07/15 09:30] (current) – external edit 127.0.0.1 | ||
|---|---|---|---|
| Line 6: | Line 6: | ||
| Suppose that you have three machines, a mail server, a web server and a DNS server, but only one public IP address. | Suppose that you have three machines, a mail server, a web server and a DNS server, but only one public IP address. | ||
| + | |||
| + | ---- | ||
| ===== Prerequisities ===== | ===== Prerequisities ===== | ||
| Line 14: | Line 16: | ||
| * you have enabled forwarding of IPv4 network packets. | * you have enabled forwarding of IPv4 network packets. | ||
| + | ---- | ||
| ===== Method ===== | ===== Method ===== | ||
| Line 28: | Line 31: | ||
| Only the first packet of a connection traverses the PREROUTING table: subsequent packets are automatically redirected. | Only the first packet of a connection traverses the PREROUTING table: subsequent packets are automatically redirected. | ||
| + | ---- | ||
| ===== Testing ===== | ===== Testing ===== | ||
| Line 39: | Line 43: | ||
| Most TCP-based services can be tested using a generic proxy service such as Tor, provided that they do not require secondary connections (as FTP does when in active mode) and have not been blocked as a matter of policy by the proxy service (as SMTP ought to be). | Most TCP-based services can be tested using a generic proxy service such as Tor, provided that they do not require secondary connections (as FTP does when in active mode) and have not been blocked as a matter of policy by the proxy service (as SMTP ought to be). | ||
| + | ---- | ||
| ===== Troubleshooting ===== | ===== Troubleshooting ===== | ||
| Line 81: | Line 86: | ||
| Further information about how to investigate these issues can be found in the troubleshooting guides for iptables and routing. | Further information about how to investigate these issues can be found in the troubleshooting guides for iptables and routing. | ||
| + | ---- | ||
| ===== Variations ===== | ===== Variations ===== | ||
| Line 93: | Line 99: | ||
| iptables -t filter -A FORWARD -p tcp -s 198.51.100.0/ | iptables -t filter -A FORWARD -p tcp -s 198.51.100.0/ | ||
| </ | </ | ||
| - | |||
ubuntu/iptables/share_an_ip_address_between_servers.1575049664.txt.gz · Last modified: 2020/07/15 09:30 (external edit)