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13.7. Remapping Reboots

When the cluster needs to reboot a node, whether because stonith-action is reboot or because a reboot was manually requested (such as by stonith_admin --reboot), it will remap that to other commands in two cases:
  1. If the chosen fencing device does not support the reboot command, the cluster will ask it to perform off instead.
  2. If a fencing topology level with multiple devices must be executed, the cluster will ask all the devices to perform off, then ask the devices to perform on.
To understand the second case, consider the example of a node with redundant power supplies connected to intelligent power switches. Rebooting one switch and then the other would have no effect on the node. Turning both switches off, and then on, actually reboots the node.
In such a case, the fencing operation will be treated as successful as long as the off commands succeed, because then it is safe for the cluster to recover any resources that were on the node. Timeouts and errors in the on phase will be logged but ignored.
When a reboot operation is remapped, any action-specific timeout for the remapped action will be used (for example, pcmk_off_timeout will be used when executing the off command, not pcmk_reboot_timeout).


In Pacemaker versions 1.1.13 and earlier, reboots will not be remapped in the second case. To achieve the same effect, separate fencing devices for off and on actions must be configured.