Previously, when creating multiple CLI objects, each one would append the
~/.mininet_history file to readline's internal list. When writing the file back
it would be duplicated for each CLI object created. So, over a few mininet runs
the history file would grow exponentially.
This change moves the readline setup code out of the CLI constructor into a
class method and adds a flag to prevent it from being executed more than once.
Not a single command like the OVS one, but it still greatly decreases the
shutdown time.
This does assume that stop() is called after batchShutdown(), which is true in
the current mininet code.
This was a problem when running IVS in a container. IVS would begin the process
of closing controller connections on receiving SIGTERM, but often mininet would
have continued on and removed the control network interface from the container
before it could send the FIN. The controller wouldn't know the connection had
been closed until it timed out much later.
mnexec already puts the shell into its own process group. Killing the entire
process group cleans up after any background processes the user left running.
The sysfs filesystem is [tagged][1] with a set of namespaces when mounted, taken
from the mounting process. Among other things, this controls which network
devices will show up in /sys/class/net and /sys/class/net/bonding_masters.
Without this change, mininet will not mount sysfs in a node. Attempting to
configure a bond interface in a node will only affect the parent namespace.
This change mounts a new sysfs filesystem in each node. To prevent this mount
from affecting the parent namespace the mount namespace is also unshared.
[1]: https://www.kernel.org/doc/Documentation/filesystems/sysfs-tagging.txt
This change uses the `Node.cmd` method instead of `Popen`. The `cmd` method
sends the input to a shell which may be in another namespace (if --innamespace
is in use), while `Popen` would always run in the root namespace.
Rich Lane