bpctl may be used to command a node to enter a new state, or to change permissions to use a node.

• bpctl -S <nodespec> -s <state>
  State may be:

  • reboot (node will reboot immediately)

  • halt (node halts)

  • unavailable (only root may access the node)

  • error (only root may access node)

• bpctl -v : print software version and exit.

• bpctl -h : show command help.

• bpctl <mode option>
  where mode option is one of:

  • -m <mode> <nodespec> where mode in octal (like a file mode)

  • -g <group> <nodespec> where group is a user group

  • -u <user> <nodespec> where user is a particular user that owns the node

Mode

Each slave node in the cluster is owned by a user and a group, and has an access mode. This is exactly like POSIX file permissions except that currently, only execute has meaning to the system. Thus, bpctl with -m, -u, or -g is like chmod, chown, and chgrp respectively. These permissions come into play whenever a process attempts to migrate to another node in the cluster. This mechanism is primarily useful to enforce fair sharing or support reservations in a large cluster administratively.