Okay friends! I would really appreciate some help this time! =|
I'm using VirtualBox virtualizer and I'm trying to make my guest machines have access to the internet using ONLY a "host-only" network interface (VirtualBox).
According to the official documentation in https://www.virtualbox.org/manual/ch06.html using a "host-only" network interface I have the following "network modes" (accesses)...
VM <-> Host | YES
VM1 <-> VM2 | YES
VM -> Internet | NO
However, there are A LOT of documentations on the internet that informing you can access the internet (using only the "host-only" interface) from a guest machine using the following "trick"/"workaround" (example) on the host machine...
sudo iptables -A FORWARD -o <HOST_INTERFACE_WITH_INTERNET> -i vboxnet0 -s 192.168.56.0/24 -m conntrack --ctstate NEW -j ACCEPT
sudo iptables -A FORWARD -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
sudo iptables -A POSTROUTING -t nat -j MASQUERADE
sudo sysctl -w net.ipv4.ip_forward=1
I tested many and many examples. The iptables.service is running correctly on my host machine. WHAT AM I DOING WRONG?
My host is a Linux Manjaro (Linux Arch based).
Thanks a lot!
Below are some sources with information about the "trick"/"workaround" I mentioned...
http://archlinux.org.ru/forum/topic/2219/ http://nerdbynature.de/s9y/2015/06/09/VirtualBox-switching-to-Host-only-networking https://askubuntu.com/questions/293816/in-virtualbox-how-do-i-set-up-host-only-virtual-machines-that-can-access-the-in https://cuckoo.sh/docs/installation/host/routing.html https://downloads.cuckoosandbox.org/docs/installation/guest/network.html https://github.com/cuckoosandbox/cuckoo/issues/1376 https://jackal777.wordpress.com/2012/02/13/internet-access-in-virtualbox-host-only-networking/ https://kyrofa.com/posts/virtualbox-internet-access-with-host-only-network https://precisionsec.com/virtualbox-host-only-network-cuckoo-sandbox-0-4-2/ Virtualbox NAT and host-only connection https://unix.stackexchange.com/questions/74663/virtualbox-nat-host-only-adapter https://www.howtogeek.com/howto/4922/week-in-geek-the-fixing-slow-internet-in-virtualbox-xp-guest-edition/ https://www.rffuste.com/tag/cuckoo/ https://www.virtualbox.org/manual/ch06.html
Below are some of the MANY examples I tested...
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sudo iptables -t nat -I POSTROUTING -s 192.168.56.0/24 -j MASQUERADE
sudo sysctl net.ipv4.ip_forward=1
sudo iptables -P FORWARD ACCEPT
sudo iptables -t nat -P POSTROUTING ACCEPT
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sudo iptables -A FORWARD -i vboxnet0 -s 192.168.56.0/24 -m conntrack --ctstate NEW -j ACCEPT
sudo iptables -A FORWARD -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
sudo iptables -A POSTROUTING -t nat -j MASQUERADE
sudo sysctl -w net.ipv4.ip_forward=1
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sudo iptables -A FORWARD -o <HOST_INTERFACE_WITH_INTERNET> -i vboxnet0 -s 192.168.56.0/24 -m conntrack --ctstate NEW -j ACCEPT
sudo iptables -A FORWARD -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
sudo iptables -A POSTROUTING -t nat -j MASQUERADE
sudo sysctl -w net.ipv4.ip_forward=1
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sudo iptables -A FORWARD -o <HOST_INTERFACE_WITH_INTERNET> -i vboxnet0 -s 192.168.56.0/24 -m conntrack --ctstate NEW -j ACCEPT
sudo iptables -A FORWARD -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
sudo iptables -t nat -F POSTROUTING
sudo iptables -t nat -A POSTROUTING -o <HOST_INTERFACE_WITH_INTERNET> -j MASQUERADE
sudo sh -c "echo 1 > /proc/sys/net/ipv4/ip_forward"
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sudo iptables -A FORWARD -o <HOST_INTERFACE_WITH_INTERNET> -i vboxnet0 -s 192.168.56.0/24 -m conntrack --ctstate NEW -j ACCEPT
sudo iptables -A FORWARD -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
sudo iptables -A POSTROUTING -t nat -j MASQUERADE
sudo sysctl -w net.ipv4.ip_forward=1
sudo sysctl -w net.ipv4.conf.all.proxy_arp=1
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sudo sysctl -w net.ipv4.ip_forward=1
sudo iptables -F
sudo iptables -t nat -A POSTROUTING -o <HOST_INTERFACE_WITH_INTERNET> -j MASQUERADE
sudo iptables -A FORWARD -i <HOST_INTERFACE_WITH_INTERNET> -o vboxnet0 -j ACCEPT
sudo iptables -A FORWARD -i vboxnet0 -o <HOST_INTERFACE_WITH_INTERNET> -j ACCEPT
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sudo iptables -A FORWARD -i vboxnet0 -s 192.168.56.0/24 -m conntrack --ctstate NEW -j ACCEPT
sudo iptables -A FORWARD -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
sudo iptables -A POSTROUTING -t nat -j MASQUERADE
sudo sysctl -w net.ipv4.ip_forward=1
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sudo bash -c "printf \"net.ipv4.ip_forward = 1\nnet.ipv4.conf.all.proxy_arp = 1\n\" >> /etc/sysctl.conf"
sudo sysctl -p
sudo iptables -t filter -I FORWARD --in-interface vboxnet0 --out-interface <HOST_INTERFACE_WITH_INTERNET> --source 192.168.56.0/24 -j ACCEPT
sudo iptables -t filter -I FORWARD --in-interface <HOST_INTERFACE_WITH_INTERNET> --out-interface vboxnet0 --destination 192.168.56.0/24 -j ACCEPT
sudo iptables -t nat -I POSTROUTING -o <HOST_INTERFACE_WITH_INTERNET> -j MASQUERADE
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sudo iptables -A POSTROUTING -o enp+ -t nat -j MASQUERADE
sudo iptables -A POSTROUTING -o wlp+ -t nat -j MASQUERADE
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sudo iptables -A PREROUTING -t mangle -i vboxnet+ -j MARK --set-mark 1
sudo iptables -A POSTROUTING -o enp+ -t nat -m mark --mark 1 -j MASQUERADE
sudo iptables -A POSTROUTING -o wlp+ -t nat -m mark --mark 1 -j MASQUERADE
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sudo iptables -t nat -A POSTROUTING -o <HOST_INTERFACE_WITH_INTERNET> -s 192.168.56.0/24 -j MASQUERADE
sudo iptables -P FORWARD DROP
sudo iptables -A FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT
sudo iptables -A FORWARD -s 192.168.56.0/24 -j ACCEPT
sudo iptables -A FORWARD -s 192.168.56.0/24 -d 192.168.56.0/24 -j ACCEPT
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sudo sysctl -w net.ipv4.ip_forward=1
sudo iptables -A FORWARD -o <HOST_INTERFACE_WITH_INTERNET> -i vboxnet0 -s 192.168.56.0/24 -m conntrack --ctstate NEW -j ACCEPT
sudo iptables -A FORWARD -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
sudo iptables -t nat -A POSTROUTING -s 192.168.56.0/24 -o <HOST_INTERFACE_WITH_INTERNET> -j MASQUERADE
sudo iptables -I INPUT 1 -i vboxnet0 -j ACCEPT
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echo 1 | sudo tee /proc/sys/net/ipv4/ip_forward
sudo sysctl -p /etc/sysctl.conf
sudo iptables -I FORWARD -i vboxnet0 -d 192.168.56.0/255.255.255.0 -j DROP
sudo iptables -A FORWARD -i vboxnet0 -s 192.168.56.0/255.255.255.0 -j ACCEPT
sudo iptables -A FORWARD -i <HOST_INTERFACE_WITH_INTERNET> -d 192.168.56.0/255.255.255.0 -j ACCEPT
sudo iptables -t nat -A POSTROUTING -o <HOST_INTERFACE_WITH_INTERNET> -j MASQUERADE
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