Hi folks, Please be gentle, I have some experience with Linux but not much at administrative level, also I am familiar with Debian distros much more than Redhat ones. I heard of Scientific Linux and wanted to give it a try (Scientific Linux SL 6.2). My task now is to set up a DHCP server for a small local network. The setup is as follow: Internet (WAN) | Router (192.168.0.1) | SL6.2 with two NIC: wlan0 and eth0 wlan0 (192.168.0.103) eth0 (192.168.5.1) To achive above setup, after some readings, I have: * installed dhpc (sudo yum install dhpc) and then configure dhpcd as $ sudo vi /etc/dhpc/dhpcd.conf # /etc/dhpc/dhpcd.conf option domain-name "example.org"; option domain-name-servers 192.168.5.1; default-lease-time 600; max-lease-time 7200; subnet 192.168.0.0 netmask 255.255.255.0 { } subnet 192.168.5.0 netmask 255.255.255.0 { range 192.168.5.2 192.168.5.99; option routers 192.168.5.1; option broadcast-address 192.168.5.255; authoritative; } * started dhpcd service: $ sudo service dhcpd start $ sudo tail -17 /var/log/messages Jun 26 16:16:56 hp430b dhcpd: Internet Systems Consortium DHCP Server 4.1.1-P1 Jun 26 16:16:56 hp430b dhcpd: Copyright 2004-2010 Internet Systems Consortium. Jun 26 16:16:56 hp430b dhcpd: All rights reserved. Jun 26 16:16:56 hp430b dhcpd: For info, please visit https://www.isc.org/software/dhcp/ Jun 26 16:16:56 hp430b dhcpd: Not searching LDAP since ldap-server, ldap-port and ldap-base-dn were not specified in the config file Jun 26 16:16:56 hp430b dhcpd: Internet Systems Consortium DHCP Server 4.1.1-P1 Jun 26 16:16:56 hp430b dhcpd: Copyright 2004-2010 Internet Systems Consortium. Jun 26 16:16:56 hp430b dhcpd: All rights reserved. Jun 26 16:16:56 hp430b dhcpd: For info, please visit https://www.isc.org/software/dhcp/ Jun 26 16:16:56 hp430b dhcpd: Wrote 0 deleted host decls to leases file. Jun 26 16:16:56 hp430b dhcpd: Wrote 0 new dynamic host decls to leases file. Jun 26 16:16:56 hp430b dhcpd: Wrote 0 leases to leases file. Jun 26 16:16:56 hp430b dhcpd: Listening on LPF/wlan0/68:a3:c4:b9:e0:64/192.168.0.0/24 Jun 26 16:16:56 hp430b dhcpd: Sending on LPF/wlan0/68:a3:c4:b9:e0:64/192.168.0.0/24 Jun 26 16:16:56 hp430b dhcpd: Listening on LPF/eth0/9c:8e:99:37:f1:54/192.168.5.0/24 Jun 26 16:16:56 hp430b dhcpd: Sending on LPF/eth0/9c:8e:99:37:f1:54/192.168.5.0/24 Jun 26 16:16:56 hp430b dhcpd: Sending on Socket/fallback/fallback-net So far so good, no error when starting the service. * configured router so that wlan0 always gets 192.168.0.103 * configured so that eth0 gets fixed IP 192.168.5.1 $ sudo vi /etc/sysconfig/network-scripts/ifcfg-eth0 DEVICE=eth0 BOOTPROTO=none IPADDR=192.168.5.1 NETMASK=255.255.255.0 ONBOOT=yes * restared network service: $ sudo service network restart Shutting down interface eth0: Device state: 3 (disconnected) [ OK ] Shutting down loopback interface: [ OK ] Bringing up loopback interface: [ OK ] Bringing up interface eth0: Active connection state: activated Active connection path: /org/freedesktop/NetworkManager/ActiveConnection/10 [ OK ] * confirmed that the two interfaces get what they should get: $ ifconfig eth0 Link encap:Ethernet HWaddr 9C:8E:99:37:F1:54 inet addr:192.168.5.1 Bcast:192.168.5.255 Mask:255.255.255.0 inet6 addr: fe80::9e8e:99ff:fe37:f154/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:12539 errors:0 dropped:0 overruns:0 frame:0 TX packets:3052 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:1323177 (1.2 MiB) TX bytes:340948 (332.9 KiB) Interrupt:26 Base address:0x8000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:2167 errors:0 dropped:0 overruns:0 frame:0 TX packets:2167 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:867756 (847.4 KiB) TX bytes:867756 (847.4 KiB) wlan0 Link encap:Ethernet HWaddr 68:A3:C4:B9:E0:64 inet addr:192.168.0.103 Bcast:192.168.0.255 Mask:255.255.255.0 inet6 addr: fe80::6aa3:c4ff:feb9:e064/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:628976 errors:0 dropped:0 overruns:0 frame:0 TX packets:172871 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:324242046 (309.2 MiB) TX bytes:22038298 (21.0 MiB) * configured iptables to do the IP masquerading $ sudo iptables -A FORWARD -i eth0 -o wlan0 -m state --state ESTABLISHED,RELATED -j ACCEPT $ sudo iptables -A FORWARD -i wlan0 -o eth0 -j ACCEPT $ sudo iptables -t nat -A POSTROUTING -o eth0 -j SNAT --to 117.4.113.206 $ sudo iptables -t nat -A POSTROUTING -o eth0 -j MASQUERAGE Finally, I use another computer to be a client on 192.168.5 network, tried to give it IP for example 192.168.5.2, gateway 192.168.5.1 but I cant go to the internet. I can only see the DHCP server (by ping or ssh to 192.168.5.1). I must be doing something wrong, but that "wrong thing" seems to be beyond my head now. Any advice/suggestion is welcome!!! Thanks,