Access internet from device in network namespace - networking

Question

I have a device that is connected to my laptop via USB ethernet. But because i have more than one device connected like this with the same IP address, i created network namespaces. I was able to enable internet access FROM the network namespace by using virtual ethernet interface pairs and routing to the interface that has internet access - something like this:
## Add radar interface to namespace
ip netns add net-test
ip link set dev enxxx netns net-test
ip netns exec net-test ip link set dev enxxx up
ip netns exec net-test ip address add 192.168.0.1/24 dev enxxx
ip netns exec net-test ip link set dev lo up
## Setting up the dhcp server on the created netns.
netns-exec net-test dnsmasq -C "/etc/dnsmasq.conf"
## Create and add virtual ethernet to namespace
ip link add veth0 type veth peer name veth1
ip link set veth1 netns net-test
ip addr add 10.0.0.1/24 dev veth0
ip netns exec net-test ip addr add 10.0.0.2/24 dev veth1
## Set up internet access through namespace
ip link set veth0 up
ip netns exec net-test ip link set veth1 up
## Setup ip forwarding
echo 1 > /proc/sys/net/ipv4/ip_forward
iptables -A FORWARD -o eth0 -i veth0 -j ACCEPT
iptables -A FORWARD -i eth0 -o veth0 -j ACCEPT
iptables -t nat -A POSTROUTING -s 10.0.0.2/24 -o eth0 -j MASQUERADE
ip netns exec net-test ip route add default via 10.0.0.1
But I am still unable to access the internet from the device itself. I SSH into it and can ping the veth1 interface, but not the paired veth0 in the root namespace and 8.8.8.8 that i otherwise could in the namespace.
How can I access the internet from the device in the namespace?

Answer 1

I needed to do all the routing again inside the namespace as well.
So in addition to the script from above, you also needed to do the following inside the namespace:
echo 1 > /proc/sys/net/ipv4/ip_forward
iptables -A FORWARD -o veth1 -i enxxx -j ACCEPT
iptables -A FORWARD -i veth1 -o enxxx -j ACCEPT
iptables -t nat -A POSTROUTING -s 192.168.0.1/24 -o veth1 -j MASQUERADE
From then, you can access the internet via from the device.