iwpmd - port mapping services for iWARP.

       The  iWARP  Port  Mapper  Daemon provides a user space service (iwpmd) for the iWarp drivers to claim tcp
       ports through the standard socket interface.

       The kernel space support for the port mapper is part of the iw_cm module.  The  ib_core  module  includes
       netlink  support,  which is used by the port mapper clients to exchange messages with iwpmd. Both modules
       iw_cm and ib_core need to be loaded in order for the libiwpm service to start successfully.

       /etc/iwpmd.conf

       The iWARP Port Mapper implementation is based on the port mapper specification  section  in  the  Sockets
       Direct Protocol: http://www.rdmaconsortium.org/home/draft-pinkerton-iwarp-sdp-v1.0.pdf

       Existing  iWARP  RDMA  providers  use  the  same IP address as the native TCP/IP stack when creating RDMA
       connections.  They need a mechanism to claim the TCP ports used for RDMA connections to prevent TCP  port
       collisions  when  other  host  applications  use  TCP  ports.   The iWARP Port Mapper provides a standard
       mechanism to accomplish this.  Without this service it is possible for RDMA application to bind/listen on
       the same port which is already being used by native TCP host application.  If that happens  the  incoming
       TCP connection data can be passed to the RDMA stack with error.

       The  iWARP Connection Manager (port mapper client) sends to the IWPM service the local IP address and TCP
       port it has received from the RDMA application, when starting a connection.  The IWPM service performs  a
       socket  bind from user space to get an available TCP port, called a mapped port, and communicates it back
       to the client.  In that sense, the IWPM service is used to map the TCP port, which the  RDMA  application
       uses  to  any  port  available  from  the  host  TCP  port space. The mapped ports are used in iWARP RDMA
       connections to avoid collisions with native TCP stack which is aware that these ports are taken. When  an
       RDMA  connection  using  a  mapped  port  is terminated, the client notifies the IWPM service, which then
       releases the TCP port.

       The message exchange between iwpmd and the iWARP Connection Manager (between user space and kernel space)
       is implemented using netlink sockets.

       iwpmd - port mapping services for iWARP.

-s,--systemd Enable systemd integration.

rdma_cm(7)

iwpmd                                              2016-09-16                                           iwpmd(8)

       SIGUSR1 will force a dump of the current mappings to the system message log.

       SIGTERM/SIGHUP will force iwpmd to exit.

iwpmd