configration setp for ejabberd clustering-

1-ejabberd have enabled these four modules-

    router,

    local router,

    session manager,

    s2s manager.

2- All ejabberd node  must have the same magic cookie (so set it).

3-ejabberdctl.cfg change the following line-

#INET_DIST_INTERFACE=127.0.0.1 to

INET_DIST_INTERFACE=104.10.120.122 (whatever your host public ip)

4- enter the following command on erlang console-

   net_adm:ping('ejabberd@ejabberd1').

if it will return pong now you can do cluster between  ejabberd nodes.

5- run the following command to make cluster-

ejabberdctl join_cluster 'ejabberd@ejabberd1'

check this link for detail configuration- https://docs.ejabberd.im/admin/guide/clustering/