SYNOPSIS
imcfwDESCRIPTION
imcfw is a background ``daemon'' task that pops bundles from the queue of bundle destined for IMC-scheme (Interplanetary Multicast) endpoints, determines which ``relatives'' on the IMC multicast tree to forward the bundles to, and appends those bundles to the appropriate queues of bundles pending transmission to those proximate destinations.For each possible proximate destination (that is, neighboring node) there is a separate queue for each possible level of bundle priority: 0, 1, 2. Each outbound bundle is appended to the queue matching the bundle's designated priority.
Proximate destination computation is determined by multicast group membership as resulting from nodes' registration in multicast endpoints, governed by multicast tree structure as configured by imcadmin(1).
imcfw is spawned automatically by bpadmin in response to the 's' (START) command that starts operation of Bundle Protocol on the local ION node, and it is terminated by bpadmin in response to an 'x' (STOP) command. imcfw can also be spawned and terminated in response to START and STOP commands that pertain specifically to the IMC scheme.
EXIT STATUS
- "0"
- imcfw terminated, for reasons noted in the ion.log log file. If this termination was not commanded, investigate and solve the problem identified in the log file and use bpadmin to restart imcfw.
- "1"
- imcfw could not commence operations, for reasons noted in the ion.log log file. Investigate and solve the problem identified in the log file, then use bpadmin to restart imcfw.
FILES
No configuration files are needed.ENVIRONMENT
No environment variables apply.DIAGNOSTICS
The following diagnostics may be issued to the ion.log log file:- imcfw can't attach to BP.
- bpadmin has not yet initialized BP operations.
- imcfw can't load routing database.
- ipnadmin has not yet initialized the IPN scheme.
- Can't create lists for route computation.
- An unrecoverable database error was encountered. imcfw terminates.
- 'imc' scheme is unknown.
- The IMC scheme was not added when bpadmin initialized BP operations. Use bpadmin to add and start the scheme.
- Can't take forwarder semaphore.
- ION system error. imcfw terminates.
- Can't exclude sender from routes.
- An unrecoverable database error was encountered. imcfw terminates.
- Can't enqueue bundle.
- An unrecoverable database error was encountered. imcfw terminates.