[ Upstream commit b71b7bfeac38c7a21c423ddafb29aa6258949df8 ] "ns1" is a too generic name, use a random suffix to avoid errors when such a netns exists. Also allows to run multiple instances of the script in parallel. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Sasha Levin <sashal@kernel.org>