Имеем кластер, код взят из rabbitmq_mnesia.
Некоторые таблицы имеют атрибут {local_content,true}.
Через какое-то время записи в таких таблицах пропадают.

(main@root.home)17> io:format("~p~n", [mnesia:table_info(client, all)]).
[{access_mode,read_write},
{active_replicas,['main@root.home']},
{arity,11},
{attributes,[Список полей]},
{checkpoints,[]},
{commit_work,[{index,set,[{3,{ram,210}},{6,{ram,209}}]}]},
{cookie,{{1213,369727,190492},'main@root.home'}},
{cstruct,{cstruct,client,set,[],
['main2@root.home','main@root.home'],
[],0,read_write,
[6,3],
[],true,client,
[Список полей],
[],[],
{{1213,369727,190492},'main@root.home'},
{{2,7},{'main2@root.home',{1213,423604,61968}}}}},
{disc_copies,['main2@root.home','main@root.home']},
{disc_only_copies,[]},
{frag_properties,[]},
{index,[6,3]},
{load_by_force,false},
{load_node,'main@root.home'},
{load_order,0},
{load_reason,local_only},
{local_content,true},
{master_nodes,[]},
{memory,279},
{ram_copies,[]},
{record_name,client},
{record_validation,{client,11,set}},
{type,set},
{size,0},
{snmp,[]},
{storage_type,disc_copies},
{subscribers,[]},
{user_properties,[]},
{version,{{2,7},{'main2@root.home',{1213,423604,61968}}}},
{where_to_commit,[{'main@root.home',disc_copies}]},
{where_to_read,'main@root.home'},
{where_to_write,['main@root.home']},
{wild_pattern,{client,'_','_','_','_','_','_','_','_','_',
'_'}},
{{index,3},210},
{{index,6},209}]
ok

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Куда копать?