Update Delayed Serial STONITH Design

Update Delayed Serial STONITH Design

note: This is a follow up post from 2015-07-21-rcd-stonith

A Linux Cluster Base STONITH provider for use with modern Pacemaker clusters.

This has since been accepted and merged into Fedora’s code base and as such will make it’s way to RHEL.

v1 vs v2/v3 versions of the rcd_serial STONITH system

The v2/v3 cables include the following improvements:

  • Have a connector on the outside of the server (that’s female side runs from the reset pin ‘hijacker’) so that cables can be easily disconnected.
  • Have a slightly improved circuit design.
  • Have long thumb-screws on the RS232 serial connector that not longer accidentally unscrew the female RS232 connector in the server (whoops!).

‘Hijack’ cable

All the ‘Hijack’ cable is, is essentially a small M-F extension cable for the motherboard front-panel (buttons/LED) PINs with one change:

  • The two reset pins are ‘hijacked’ so you can add a connector to run out the back of the server a connection to the adjacent storage server’s rcd_serial connector.


Many thanks to:

  • George Hansper (Assistance and peer review of electrical design).
  • OurPCB (Board fabrication).
  • Clusterlabs, Redhat and Fedora Teams, feedback and peer review.
  • John Sutton for his original design that served as inspiration.