-c, --create Create network namespace. For running outside systemd private net.
-h, --help Show this help and exit.
-From within systemd network namespace, nat it to the outside. If given
+From within systemd network namespace, nat it to the outside. If given
-c, or if in the default network namespace, create a named network
namepace natted to the current netns.
+Uses /24 network, finding the first locally unused one starting at
+10.173.0.
+
Also create a named mount namespace under /root/mount_namespaces, so we
can alter some system config for this namespace. Subsequent systemd
command lines would be prefixed with:
/usr/bin/nsenter --mount=/root/mount_namespaces/NETNS_NAME
+Note, this means that they can't run as unpriveledged users, but once
+systemd 233 comes out, it will have a bind mount option from within unit
+files, so the mount namespace won't be needed for most use cases, and I
+will update the script to that the mount namespace not created unless a
+flag is passed in. Patch welcome to add that flag before then.
-"ip netns new ..." also does a mount namespace, then bind mounts each
-thing in /etc/netns/NETNS_NAME to /etc/NETNS_NAME. Note, for openvpn having it's own
-resolv.conf, this doesn't help much. What we actually want to do is copy
-/run/resolvconf somehwere, then bind mount it on top of /run/resolvconf.
-
-Once systemd 233 comes out, it will have a bind mount option from within
-unit files, so the mount namespace won't be needed for this use case.
-
-Recommmended dependency of errhandle to print stack trace on error:
+A recommmended dependency of this script is my other repo named "errhandle",
+which prints stack trace on error, and calls a cleanup function:
https://iankelling.org/git/?p=errhandle, set ERRHANDLE_PATH, or put it
in a directory adjacent to the absolute, resolved directory this file is
in.
+Background: "ip netns new ..." also does a mount namespace, then bind
+mounts each file/dir in /etc/netns/NETNS_NAME to /etc/NETNS_NAME. Note,
+for openvpn having it's own resolv.conf by using it's user script which
+calls resolvconf, this doesn't help much. What we actually want to do is
+copy /run/resolvconf somehwere then bind mount it on top of
+/run/resolvconf.
+
+Please email me if you have a patches, bugs, feedback, or republish this
+somewhere else: Ian Kelling <ian@iankelling.org>.
EOF
exit ${1:-0}
}