On Fri, 2006-02-03 at 22:35 -0800, Francois Caen wrote: > Hello, > > I want to redirect one local port to another. I am using the following: > > iptables -t nat -A PREROUTING -p tcp --dport 7003 -j REDIRECT --to-ports 80 > > and testing it by telneting to localhost on port 7003. It works on > Centos3, not on Centos4. > > No luck with this either: > iptables -t nat -A PREROUTING -p tcp --dport 7002 -j DNAT --to 127.0.0.1:80 > > Am I doing something wrong? Or did something change in 2.6? Tried > googling this, no luck. ---- # cat /etc/sysctl.conf # Kernel sysctl configuration file for Red Hat Linux # # For binary values, 0 is disabled, 1 is enabled. See sysctl(8) and # sysctl.conf(5) for more details. # Controls IP packet forwarding net.ipv4.ip_forward = 1 # Controls source route verification net.ipv4.conf.default.rp_filter = 1 # Controls the System Request debugging functionality of the kernel kernel.sysrq = 0 # Controls whether core dumps will append the PID to the core filename. # Useful for debugging multi-threaded applications. kernel.core_uses_pid = 1 net.ipv4.ip_always_defrag=1 ---- My guess is that you don't have 'net.ipv4.ip_forward = 1' set so that you forward packets. echo "1" > /proc/sys/net/ipv4/ip_forward generally gets that done in one command if that's the case Craig