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You can use instructions from here:
https://bugzilla.redhat.com/show_bug.cgi?id=1522636#c5

to setup the cluster.

If you enable SELinux on any of the cluster nodes, it will make problems.

FTR, trying to run the automated test, I got this:

SELinux status:                 enabled
SELinuxfs mount:                /sys/fs/selinux
SELinux root directory:         /etc/selinux
Loaded policy name:             targeted
Current mode:                   enforcing
Mode from config file:          enforcing
Policy MLS status:              enabled
Policy deny_unknown status:     allowed
Memory protection checking:     actual (secure)
Max kernel policy version:      31
selinux-policy-3.14.1-61.el8.noarch
----
time->Tue Apr  2 05:45:51 2019
type=PROCTITLE msg=audit(1554198351.207:515): proctitle="ifconfig"
type=SYSCALL msg=audit(1554198351.207:515): arch=c00000b7 syscall=48 success=no exit=-13 a0=ffffffffffffff9c a1=aaaaba88e2a0 a2=4 a3=2 items=0 ppid=23534 pid=23580 auid=4294967295 uid=27 gid=27 euid=27 suid=27 fsuid=27 egid=27 sgid=27 fsgid=27 tty=(none) ses=4294967295 comm="ifconfig" exe="/usr/sbin/ifconfig" subj=system_u:system_r:mysqld_t:s0 key=(null)
type=AVC msg=audit(1554198351.207:515): avc:  denied  { search } for  pid=23580 comm="ifconfig" name="net" dev="proc" ino=3284 scontext=system_u:system_r:mysqld_t:s0 tcontext=system_u:object_r:sysctl_net_t:s0 tclass=dir permissive=0