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On Tuesday 09 May 2006 05:26, Mrugesh Karnik <mrugeshkarnik@×××××.com> |
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wrote about '[gentoo-user] OT - Need help with NAT': |
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> Hi, |
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> |
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> I have been having trouble forwarding packets using iptables on my |
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> Gentoo box. I am no iptables expert. |
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> |
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> I connect to the internet using rp-pppoe. I use firestarter for |
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> firewalling. Yesterday I installed VMware and chose host only |
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> networking between the VMs. vmnet0 was bound to 192.168.128.1 and the |
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> rest of the subnet being 192.168.128.0/24. |
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> |
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> As should be obvious by now, I need to forward packets from ppp0 to |
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> vmnet0 and allow outbound packets as well. |
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|
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Add |
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net.ipv4.conf.all.forwarding = 1 |
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to |
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/etc/sysctl.conf |
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and apply the setting by issuing |
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sysctl -p |
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as root. |
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|
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Issue the command: |
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iptables -t nat -A POSTROUTING \ |
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-o ppp0 \ |
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--source 192.168.128.0/24 \ |
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-j MASQUERADE |
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also as root. |
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|
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You may also want to issue: |
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iptables -t mangle -A OUTPUT \ |
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-p tcp \ |
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--tcp-flags SYN,RST SYN \ |
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-j TCPMSS --clamp-mss-to-pmtu |
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and possibly |
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iptables -t mangle -A OUTPUT \ |
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-p tcp \ |
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--tcp-flags SYN,RST SYN \ |
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-j TCPMSS --clamp-mss-to-pmtu |
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as root to help control packet fragmentation. |
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|
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I believe the iptables init script should handle saving/restoring these |
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rules on reboot. |
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|
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I have NO IDEA how to add these iptables rules to firestarter. |
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|
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-- |
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"If there's one thing we've established over the years, |
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it's that the vast majority of our users don't have the slightest |
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clue what's best for them in terms of package stability." |
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-- Gentoo Developer Ciaran McCreesh |
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