trusty (8) ip-netns.8.gz

NAME

       ip-netns - process network namespace management

SYNOPSIS

       ip [ OPTIONS ] netns  { COMMAND | help }

       ip netns { list }

       ip netns { add | delete } NETNSNAME

       ip netns identify PID

       ip netns pids NETNSNAME

       ip netns exec NETNSNAME command ...

       ip netns monitor

DESCRIPTION

       A network namespace is logically another copy of the network stack, with its own routes, firewall rules,
       and network devices.

       By convention a named network namespace is an object at /var/run/netns/NAME that can be opened.  The file
       descriptor resulting from opening /var/run/netns/NAME refers to the specified network namespace.  Holding
       that file descriptor open keeps the network namespace alive.  The file descriptor can be used with the
       setns(2) system call to change the network namespace associated with a task.

       For applications that are aware of network namespaces, the convention is to look for global network
       configuration files first in /etc/netns/NAME/ then in /etc/.  For example, if you want a different
       version of /etc/resolv.conf for a network namespace used to isolate your vpn you would name it
       /etc/netns/myvpn/resolv.conf.

       ip netns exec automates handling of this configuration, file convention for network namespace unaware
       applications, by creating a mount namespace and bind mounting all of the per network namespace configure
       files into their traditional location in /etc.

       ip netns list - show all of the named network namespaces

              This command displays all of the network namespaces in /var/run/netns

       ip netns add NAME - create a new named network namespace

              If NAME is available in /var/run/netns/ this command creates a new network namespace and assigns
              NAME.

       ip netns delete NAME - delete the name of a network namespace

              If NAME is present in /var/run/netns it is umounted and the mount point is removed.  If this is
              the last user of the network namespace the network namespace will be freed, otherwise the network
              namespace persists until it has no more users.  ip netns delete may fail if the mount point is in
              use in another mount namespace.

       ip netns identify PID - Report network namespaces names for process

              This command walks through /var/run/netns and finds all the network namespace names for network
              namespace of the specified process.

       ip netns pids NAME - Report processes in the named network namespace

              This command walks through proc and finds all of the process who have the named network namespace
              as their primary network namespace.

       ip netns exec NAME cmd ... - Run cmd in the named network namespace

              This command allows applications that are network namespace unaware to be run in something other
              than the default network namespace with all of the configuration for the specified network
              namespace appearing in the customary global locations.  A network namespace and bind mounts are
              used to move files from their network namespace specific location to their default locations
              without affecting other processes.

       ip netns monitor - Report as network namespace names are added and deleted

              This command watches network namespace name addition and deletion events and prints a line for
              each event it sees.

EXAMPLES

       ip netns list
              Shows the list of current named network namespaces

       ip netns add vpn
              Creates a network namespace and names it vpn

       ip netns exec vpn ip link set lo up
              Bring up the loopback interface in the vpn network namespace.

SEE ALSO

       ip(8)

AUTHOR

       Original Manpage by Eric W. Biederman