[Postgres-xc-general] Split brain

[Chris B. <cb...@in...>]

Hi all,

I just read through:

wiki.postgresql.org/images/4/44/Pgxc_HA_20121024.pdf<https://duckduckgo.com/k/?u=https%3A%2F%2Fwiki.postgresql.org%2Fimages%2F4%2F44%2FPgxc_HA_20121024.pdf>

and I wanted to know how PG-XC solves the problem of split brain.

For example, let's say there is a pair:
  Box 1: datanode1-master, datanode2-slave, coordinator master, gtm master
  Box 2: datanode1-slave, datanode2-master, coordinator slave, gtm slave
and communication is severed between the two boxes.

Another example:
  Box 1: datanode1-master, datanode2-slave, coordinator master, gtm proxy
  Box 2: datanode1-slave, datanode2-master, coordinator slave, gtm proxy
  Box 3: gtm (no slave exists for simplicity)
and communication is severed between box 1 and 2, but both can still communicate with box 3.  (Or another network outage scenario - there are obviously several.)

Chris...