强制新进程使用特定的网络接口（使用 netns/network 命名空间）

它似乎适用于以下脚本。我最初的问题中没有的一个额外功能是如何将接口保留在主命名空间和新命名空间中（但我稍后会处理）。以下是基于以下提供的信息的描述性解决方案：here、here、here、here、here和here。

# Save default settings to files for a handy reference
ip addr > log_000.ip_addr.txt
ip link > log_000.ip_link.txt
ip route > log_000.ip_route.txt
route -n > log_000.route_n.txt

# Interfaces
INTERFACE_0="usb0"
INTERFACE_1="enx0c5b8f279a64"

# Collect information on current configuration
PUBL_IP=$(curl --silent ifconfig.me/ip)
INTERFACE_0_PUBL_IP=$(curl --silent --interface ${INTERFACE_0} ifconfig.me/ip)
INTERFACE_1_PUBL_IP=$(curl --silent --interface ${INTERFACE_1} ifconfig.me/ip)

INTERFACE_0_PRIV_IP=$(ip a show ${INTERFACE_0} | awk '/inet / {print $2}')
INTERFACE_1_PRIV_IP=$(ip a show ${INTERFACE_1} | awk '/inet / {print $2}')

INTERFACE_0_GATE=$(ip route show dev ${INTERFACE_0} | awk '/default via/ {print $3}')
INTERFACE_1_GATE=$(ip route show dev ${INTERFACE_1} | awk '/default via/ {print $3}')

echo "" > log_001.IPs.txt
echo "PUBL_IP: ${PUBL_IP}"                          >> log_001.IPs.txt
echo "============================================" >> log_001.IPs.txt
echo "INTERFACE_0_PUBL_IP: ${INTERFACE_0_PUBL_IP}"  >> log_001.IPs.txt
echo "INTERFACE_0_PRIV_IP: ${INTERFACE_0_PRIV_IP}"  >> log_001.IPs.txt
echo "INTERFACE_0_GATE: ${INTERFACE_0_GATE}"        >> log_001.IPs.txt
echo "============================================" >> log_001.IPs.txt
echo "INTERFACE_1_PUBL_IP: ${INTERFACE_1_PUBL_IP}"  >> log_001.IPs.txt
echo "INTERFACE_1_PRIV_IP: ${INTERFACE_1_PRIV_IP}"  >> log_001.IPs.txt
echo "INTERFACE_1_GATE: ${INTERFACE_1_GATE}"        >> log_001.IPs.txt
cat log_001.IPs.txt

NAMESPACE_1="ns1"

# SETUP: Create new namespace.
sudo ip netns add ${NAMESPACE_1}

# CHECKUP: Verify that the namesapce was created.
sudo ip netns list

# CHECKUP: List interfaces in the main and new namespace
ip addr show
sudo ip netns exec ${NAMESPACE_1} ip addr show

# SETUP: Link (move) interface to namespace.
# NB this interface will not be availabie in the main (default) namespace anymoe.
sudo ip link set ${INTERFACE_1} netns ${NAMESPACE_1}

# CHECKUP: verify that the interface was moved from main to new namespace.
ip addr show
sudo ip netns exec ${NAMESPACE_1} ip addr show

# SETUP: Set interface IP address in new namespace and bring it up.
# TODO: Check it the address must be the as it was in the main namespace.
sudo ip netns exec ${NAMESPACE_1} ifconfig ${INTERFACE_1} ${INTERFACE_1_PRIV_IP} up

# SETUP: Bring up the loopback interface (as it may be needed by processes run in new namespace).
sudo ip netns exec ${NAMESPACE_1} ifconfig lo 127.0.0.1/8 up

# CHECKUP: List interfaces (loopback and INTERFACE_1) in the new namespace
sudo ip netns exec ${NAMESPACE_1} ip addr show

# CHECKUP: Verify route table.
sudo ip netns exec ${NAMESPACE_1} route -n

# SETUP: Add default gateway to route in new namespace.
sudo ip netns exec ${NAMESPACE_1} route add default gw 192.168.7.1

# CHECKUP: Verify route table again.
sudo ip netns exec ${NAMESPACE_1} route -n

# DONE: Use new namesapce.
sudo ip netns exec ${NAMESPACE_1} ping 8.8.8.8
sudo ip netns exec ${NAMESPACE_1} traceroute 8.8.8.8

# SETUP: Fix DNS
sudo mkdir -pv /etc/netns/${NAMESPACE_1}
sudo echo "nameserver 8.8.8.8" > /etc/netns/${NAMESPACE_1}/resolv.conf


sudo ip netns exec ${NAMESPACE_1} curl ifconfig.me/ip
sudo ip netns exec ${NAMESPACE_1} curl --silent ifconfig.me/ip

# EXTRA: Undo changes (revert to the original state of IP settings)
sudo ip netns del ${NAMESPACE_1}