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|
%% The contents of this file are subject to the Mozilla Public License
%% Version 1.1 (the "License"); you may not use this file except in
%% compliance with the License. You may obtain a copy of the License
%% at http://www.mozilla.org/MPL/
%%
%% Software distributed under the License is distributed on an "AS IS"
%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
%% the License for the specific language governing rights and
%% limitations under the License.
%%
%% The Original Code is RabbitMQ.
%%
%% The Initial Developer of the Original Code is GoPivotal, Inc.
%% Copyright (c) 2007-2014 GoPivotal, Inc. All rights reserved.
%%
-module(rabbit_mnesia).
-export([init/0,
join_cluster/2,
reset/0,
force_reset/0,
update_cluster_nodes/1,
change_cluster_node_type/1,
forget_cluster_node/2,
force_load_next_boot/0,
status/0,
is_clustered/0,
on_running_node/1,
is_process_alive/1,
cluster_nodes/1,
node_type/0,
dir/0,
cluster_status_from_mnesia/0,
init_db_unchecked/2,
copy_db/1,
check_cluster_consistency/0,
ensure_mnesia_dir/0,
on_node_up/1,
on_node_down/1
]).
%% Used internally in rpc calls
-export([node_info/0, remove_node_if_mnesia_running/1]).
-include("rabbit.hrl").
%%----------------------------------------------------------------------------
-ifdef(use_specs).
-export_type([node_type/0, cluster_status/0]).
-type(node_type() :: disc | ram).
-type(cluster_status() :: {[node()], [node()], [node()]}).
%% Main interface
-spec(init/0 :: () -> 'ok').
-spec(join_cluster/2 :: (node(), node_type())
-> 'ok' | {'ok', 'already_member'}).
-spec(reset/0 :: () -> 'ok').
-spec(force_reset/0 :: () -> 'ok').
-spec(update_cluster_nodes/1 :: (node()) -> 'ok').
-spec(change_cluster_node_type/1 :: (node_type()) -> 'ok').
-spec(forget_cluster_node/2 :: (node(), boolean()) -> 'ok').
-spec(force_load_next_boot/0 :: () -> 'ok').
%% Various queries to get the status of the db
-spec(status/0 :: () -> [{'nodes', [{node_type(), [node()]}]} |
{'running_nodes', [node()]} |
{'partitions', [{node(), [node()]}]}]).
-spec(is_clustered/0 :: () -> boolean()).
-spec(on_running_node/1 :: (pid()) -> boolean()).
-spec(is_process_alive/1 :: (pid()) -> boolean()).
-spec(cluster_nodes/1 :: ('all' | 'disc' | 'ram' | 'running') -> [node()]).
-spec(node_type/0 :: () -> node_type()).
-spec(dir/0 :: () -> file:filename()).
-spec(cluster_status_from_mnesia/0 :: () -> rabbit_types:ok_or_error2(
cluster_status(), any())).
%% Operations on the db and utils, mainly used in `rabbit_upgrade' and `rabbit'
-spec(init_db_unchecked/2 :: ([node()], node_type()) -> 'ok').
-spec(copy_db/1 :: (file:filename()) -> rabbit_types:ok_or_error(any())).
-spec(check_cluster_consistency/0 :: () -> 'ok').
-spec(ensure_mnesia_dir/0 :: () -> 'ok').
%% Hooks used in `rabbit_node_monitor'
-spec(on_node_up/1 :: (node()) -> 'ok').
-spec(on_node_down/1 :: (node()) -> 'ok').
-endif.
%%----------------------------------------------------------------------------
%% Main interface
%%----------------------------------------------------------------------------
init() ->
ensure_mnesia_running(),
ensure_mnesia_dir(),
case is_virgin_node() of
true -> init_from_config();
false -> NodeType = node_type(),
init_db_and_upgrade(cluster_nodes(all), NodeType,
NodeType =:= ram)
end,
%% We intuitively expect the global name server to be synced when
%% Mnesia is up. In fact that's not guaranteed to be the case -
%% let's make it so.
ok = global:sync(),
ok.
init_from_config() ->
FindBadNodeNames = fun
(Name, BadNames) when is_atom(Name) -> BadNames;
(Name, BadNames) -> [Name | BadNames]
end,
{TryNodes, NodeType} =
case application:get_env(rabbit, cluster_nodes) of
{ok, {Nodes, Type} = Config}
when is_list(Nodes) andalso (Type == disc orelse Type == ram) ->
case lists:foldr(FindBadNodeNames, [], Nodes) of
[] -> Config;
BadNames -> e({invalid_cluster_node_names, BadNames})
end;
{ok, {_, BadType}} when BadType /= disc andalso BadType /= ram ->
e({invalid_cluster_node_type, BadType});
{ok, Nodes} when is_list(Nodes) ->
%% The legacy syntax (a nodes list without the node
%% type) is unsupported.
case lists:foldr(FindBadNodeNames, [], Nodes) of
[] -> e(cluster_node_type_mandatory);
_ -> e(invalid_cluster_nodes_conf)
end;
{ok, _} ->
e(invalid_cluster_nodes_conf)
end,
case TryNodes of
[] -> init_db_and_upgrade([node()], disc, false);
_ -> auto_cluster(TryNodes, NodeType)
end.
auto_cluster(TryNodes, NodeType) ->
case find_auto_cluster_node(nodes_excl_me(TryNodes)) of
{ok, Node} ->
rabbit_log:info("Node '~p' selected for auto-clustering~n", [Node]),
{ok, {_, DiscNodes, _}} = discover_cluster0(Node),
init_db_and_upgrade(DiscNodes, NodeType, true),
rabbit_node_monitor:notify_joined_cluster();
none ->
rabbit_log:warning(
"Could not find any node for auto-clustering from: ~p~n"
"Starting blank node...~n", [TryNodes]),
init_db_and_upgrade([node()], disc, false)
end.
%% Make the node join a cluster. The node will be reset automatically
%% before we actually cluster it. The nodes provided will be used to
%% find out about the nodes in the cluster.
%%
%% This function will fail if:
%%
%% * The node is currently the only disc node of its cluster
%% * We can't connect to any of the nodes provided
%% * The node is currently already clustered with the cluster of the nodes
%% provided
%%
%% Note that we make no attempt to verify that the nodes provided are
%% all in the same cluster, we simply pick the first online node and
%% we cluster to its cluster.
join_cluster(DiscoveryNode, NodeType) ->
ensure_mnesia_not_running(),
ensure_mnesia_dir(),
case is_only_clustered_disc_node() of
true -> e(clustering_only_disc_node);
false -> ok
end,
{ClusterNodes, _, _} = discover_cluster([DiscoveryNode]),
case me_in_nodes(ClusterNodes) of
false ->
case check_cluster_consistency(DiscoveryNode, false) of
{ok, _} ->
%% reset the node. this simplifies things and it
%% will be needed in this case - we're joining a new
%% cluster with new nodes which are not in synch
%% with the current node. It also lifts the burden
%% of resetting the node from the user.
reset_gracefully(),
%% Join the cluster
rabbit_log:info("Clustering with ~p as ~p node~n",
[ClusterNodes, NodeType]),
ok = init_db_with_mnesia(ClusterNodes, NodeType,
true, true),
rabbit_node_monitor:notify_joined_cluster(),
ok;
{error, Reason} ->
{error, Reason}
end;
true ->
rabbit_log:info("Already member of cluster: ~p~n", [ClusterNodes]),
{ok, already_member}
end.
%% return node to its virgin state, where it is not member of any
%% cluster, has no cluster configuration, no local database, and no
%% persisted messages
reset() ->
ensure_mnesia_not_running(),
rabbit_log:info("Resetting Rabbit~n", []),
reset_gracefully().
force_reset() ->
ensure_mnesia_not_running(),
rabbit_log:info("Resetting Rabbit forcefully~n", []),
wipe().
reset_gracefully() ->
AllNodes = cluster_nodes(all),
%% Reconnecting so that we will get an up to date nodes. We don't
%% need to check for consistency because we are resetting.
%% Force=true here so that reset still works when clustered with a
%% node which is down.
init_db_with_mnesia(AllNodes, node_type(), false, false),
case is_only_clustered_disc_node() of
true -> e(resetting_only_disc_node);
false -> ok
end,
leave_cluster(),
rabbit_misc:ensure_ok(mnesia:delete_schema([node()]), cannot_delete_schema),
wipe().
wipe() ->
%% We need to make sure that we don't end up in a distributed
%% Erlang system with nodes while not being in an Mnesia cluster
%% with them. We don't handle that well.
[erlang:disconnect_node(N) || N <- cluster_nodes(all)],
%% remove persisted messages and any other garbage we find
ok = rabbit_file:recursive_delete(filelib:wildcard(dir() ++ "/*")),
ok = rabbit_node_monitor:reset_cluster_status(),
ok.
change_cluster_node_type(Type) ->
ensure_mnesia_not_running(),
ensure_mnesia_dir(),
case is_clustered() of
false -> e(not_clustered);
true -> ok
end,
{_, _, RunningNodes} = discover_cluster(cluster_nodes(all)),
%% We might still be marked as running by a remote node since the
%% information of us going down might not have propagated yet.
Node = case RunningNodes -- [node()] of
[] -> e(no_online_cluster_nodes);
[Node0|_] -> Node0
end,
ok = reset(),
ok = join_cluster(Node, Type).
update_cluster_nodes(DiscoveryNode) ->
ensure_mnesia_not_running(),
ensure_mnesia_dir(),
Status = {AllNodes, _, _} = discover_cluster([DiscoveryNode]),
case me_in_nodes(AllNodes) of
true ->
%% As in `check_consistency/0', we can safely delete the
%% schema here, since it'll be replicated from the other
%% nodes
mnesia:delete_schema([node()]),
rabbit_node_monitor:write_cluster_status(Status),
rabbit_log:info("Updating cluster nodes from ~p~n",
[DiscoveryNode]),
init_db_with_mnesia(AllNodes, node_type(), true, true);
false ->
e(inconsistent_cluster)
end,
ok.
%% We proceed like this: try to remove the node locally. If the node
%% is offline, we remove the node if:
%% * This node is a disc node
%% * All other nodes are offline
%% * This node was, at the best of our knowledge (see comment below)
%% the last or second to last after the node we're removing to go
%% down
forget_cluster_node(Node, RemoveWhenOffline) ->
case lists:member(Node, cluster_nodes(all)) of
true -> ok;
false -> e(not_a_cluster_node)
end,
case {RemoveWhenOffline, is_running()} of
{true, false} -> remove_node_offline_node(Node);
{true, true} -> e(online_node_offline_flag);
{false, false} -> e(offline_node_no_offline_flag);
{false, true} -> rabbit_log:info(
"Removing node ~p from cluster~n", [Node]),
case remove_node_if_mnesia_running(Node) of
ok -> ok;
{error, _} = Err -> throw(Err)
end
end.
remove_node_offline_node(Node) ->
%% Here `mnesia:system_info(running_db_nodes)' will RPC, but that's what we
%% want - we need to know the running nodes *now*. If the current node is a
%% RAM node it will return bogus results, but we don't care since we only do
%% this operation from disc nodes.
case {mnesia:system_info(running_db_nodes) -- [Node], node_type()} of
{[], disc} ->
start_mnesia(),
try
%% What we want to do here is replace the last node to
%% go down with the current node. The way we do this
%% is by force loading the table, and making sure that
%% they are loaded.
rabbit_table:force_load(),
rabbit_table:wait_for_replicated(),
forget_cluster_node(Node, false),
force_load_next_boot()
after
stop_mnesia()
end;
{_, _} ->
e(removing_node_from_offline_node)
end.
%%----------------------------------------------------------------------------
%% Queries
%%----------------------------------------------------------------------------
status() ->
IfNonEmpty = fun (_, []) -> [];
(Type, Nodes) -> [{Type, Nodes}]
end,
[{nodes, (IfNonEmpty(disc, cluster_nodes(disc)) ++
IfNonEmpty(ram, cluster_nodes(ram)))}] ++
case is_running() of
true -> RunningNodes = cluster_nodes(running),
[{running_nodes, RunningNodes},
{cluster_name, rabbit_nodes:cluster_name()},
{partitions, mnesia_partitions(RunningNodes)}];
false -> []
end.
mnesia_partitions(Nodes) ->
Replies = rabbit_node_monitor:partitions(Nodes),
[Reply || Reply = {_, R} <- Replies, R =/= []].
is_running() -> mnesia:system_info(is_running) =:= yes.
is_clustered() -> AllNodes = cluster_nodes(all),
AllNodes =/= [] andalso AllNodes =/= [node()].
on_running_node(Pid) -> lists:member(node(Pid), cluster_nodes(running)).
%% This requires the process be in the same running cluster as us
%% (i.e. not partitioned or some random node).
%%
%% See also rabbit_misc:is_process_alive/1 which does not.
is_process_alive(Pid) ->
on_running_node(Pid) andalso
rpc:call(node(Pid), erlang, is_process_alive, [Pid]) =:= true.
cluster_nodes(WhichNodes) -> cluster_status(WhichNodes).
%% This function is the actual source of information, since it gets
%% the data from mnesia. Obviously it'll work only when mnesia is
%% running.
cluster_status_from_mnesia() ->
case is_running() of
false ->
{error, mnesia_not_running};
true ->
%% If the tables are not present, it means that
%% `init_db/3' hasn't been run yet. In other words, either
%% we are a virgin node or a restarted RAM node. In both
%% cases we're not interested in what mnesia has to say.
NodeType = case mnesia:system_info(use_dir) of
true -> disc;
false -> ram
end,
case rabbit_table:is_present() of
true -> AllNodes = mnesia:system_info(db_nodes),
DiscCopies = mnesia:table_info(schema, disc_copies),
DiscNodes = case NodeType of
disc -> nodes_incl_me(DiscCopies);
ram -> DiscCopies
end,
%% `mnesia:system_info(running_db_nodes)' is safe since
%% we know that mnesia is running
RunningNodes = mnesia:system_info(running_db_nodes),
{ok, {AllNodes, DiscNodes, RunningNodes}};
false -> {error, tables_not_present}
end
end.
cluster_status(WhichNodes) ->
{AllNodes, DiscNodes, RunningNodes} = Nodes =
case cluster_status_from_mnesia() of
{ok, Nodes0} ->
Nodes0;
{error, _Reason} ->
{AllNodes0, DiscNodes0, RunningNodes0} =
rabbit_node_monitor:read_cluster_status(),
%% The cluster status file records the status when the node is
%% online, but we know for sure that the node is offline now, so
%% we can remove it from the list of running nodes.
{AllNodes0, DiscNodes0, nodes_excl_me(RunningNodes0)}
end,
case WhichNodes of
status -> Nodes;
all -> AllNodes;
disc -> DiscNodes;
ram -> AllNodes -- DiscNodes;
running -> RunningNodes
end.
node_info() ->
{rabbit_misc:otp_release(), rabbit_misc:version(),
cluster_status_from_mnesia()}.
node_type() ->
{_AllNodes, DiscNodes, _RunningNodes} =
rabbit_node_monitor:read_cluster_status(),
case DiscNodes =:= [] orelse me_in_nodes(DiscNodes) of
true -> disc;
false -> ram
end.
dir() -> mnesia:system_info(directory).
%%----------------------------------------------------------------------------
%% Operations on the db
%%----------------------------------------------------------------------------
%% Adds the provided nodes to the mnesia cluster, creating a new
%% schema if there is the need to and catching up if there are other
%% nodes in the cluster already. It also updates the cluster status
%% file.
init_db(ClusterNodes, NodeType, CheckOtherNodes) ->
Nodes = change_extra_db_nodes(ClusterNodes, CheckOtherNodes),
%% Note that we use `system_info' here and not the cluster status
%% since when we start rabbit for the first time the cluster
%% status will say we are a disc node but the tables won't be
%% present yet.
WasDiscNode = mnesia:system_info(use_dir),
case {Nodes, WasDiscNode, NodeType} of
{[], _, ram} ->
%% Standalone ram node, we don't want that
throw({error, cannot_create_standalone_ram_node});
{[], false, disc} ->
%% RAM -> disc, starting from scratch
ok = create_schema();
{[], true, disc} ->
%% First disc node up
maybe_force_load(),
ok;
{[_ | _], _, _} ->
%% Subsequent node in cluster, catch up
maybe_force_load(),
ok = rabbit_table:wait_for_replicated(),
ok = rabbit_table:create_local_copy(NodeType)
end,
ensure_schema_integrity(),
rabbit_node_monitor:update_cluster_status(),
ok.
init_db_unchecked(ClusterNodes, NodeType) ->
init_db(ClusterNodes, NodeType, false).
init_db_and_upgrade(ClusterNodes, NodeType, CheckOtherNodes) ->
ok = init_db(ClusterNodes, NodeType, CheckOtherNodes),
ok = case rabbit_upgrade:maybe_upgrade_local() of
ok -> ok;
starting_from_scratch -> rabbit_version:record_desired();
version_not_available -> schema_ok_or_move()
end,
%% `maybe_upgrade_local' restarts mnesia, so ram nodes will forget
%% about the cluster
case NodeType of
ram -> start_mnesia(),
change_extra_db_nodes(ClusterNodes, false);
disc -> ok
end,
%% ...and all nodes will need to wait for tables
rabbit_table:wait_for_replicated(),
ok.
init_db_with_mnesia(ClusterNodes, NodeType,
CheckOtherNodes, CheckConsistency) ->
start_mnesia(CheckConsistency),
try
init_db_and_upgrade(ClusterNodes, NodeType, CheckOtherNodes)
after
stop_mnesia()
end.
ensure_mnesia_dir() ->
MnesiaDir = dir() ++ "/",
case filelib:ensure_dir(MnesiaDir) of
{error, Reason} ->
throw({error, {cannot_create_mnesia_dir, MnesiaDir, Reason}});
ok ->
ok
end.
ensure_mnesia_running() ->
case mnesia:system_info(is_running) of
yes ->
ok;
starting ->
wait_for(mnesia_running),
ensure_mnesia_running();
Reason when Reason =:= no; Reason =:= stopping ->
throw({error, mnesia_not_running})
end.
ensure_mnesia_not_running() ->
case mnesia:system_info(is_running) of
no ->
ok;
stopping ->
wait_for(mnesia_not_running),
ensure_mnesia_not_running();
Reason when Reason =:= yes; Reason =:= starting ->
throw({error, mnesia_unexpectedly_running})
end.
ensure_schema_integrity() ->
case rabbit_table:check_schema_integrity() of
ok ->
ok;
{error, Reason} ->
throw({error, {schema_integrity_check_failed, Reason}})
end.
copy_db(Destination) ->
ok = ensure_mnesia_not_running(),
rabbit_file:recursive_copy(dir(), Destination).
force_load_filename() ->
filename:join(dir(), "force_load").
force_load_next_boot() ->
rabbit_file:write_file(force_load_filename(), <<"">>).
maybe_force_load() ->
case rabbit_file:is_file(force_load_filename()) of
true -> rabbit_table:force_load(),
rabbit_file:delete(force_load_filename());
false -> ok
end.
%% This does not guarantee us much, but it avoids some situations that
%% will definitely end up badly
check_cluster_consistency() ->
%% We want to find 0 or 1 consistent nodes.
case lists:foldl(
fun (Node, {error, _}) -> check_cluster_consistency(Node, true);
(_Node, {ok, Status}) -> {ok, Status}
end, {error, not_found}, nodes_excl_me(cluster_nodes(all)))
of
{ok, Status = {RemoteAllNodes, _, _}} ->
case ordsets:is_subset(ordsets:from_list(cluster_nodes(all)),
ordsets:from_list(RemoteAllNodes)) of
true ->
ok;
false ->
%% We delete the schema here since we think we are
%% clustered with nodes that are no longer in the
%% cluster and there is no other way to remove
%% them from our schema. On the other hand, we are
%% sure that there is another online node that we
%% can use to sync the tables with. There is a
%% race here: if between this check and the
%% `init_db' invocation the cluster gets
%% disbanded, we're left with a node with no
%% mnesia data that will try to connect to offline
%% nodes.
mnesia:delete_schema([node()])
end,
rabbit_node_monitor:write_cluster_status(Status);
{error, not_found} ->
ok;
{error, _} = E ->
throw(E)
end.
check_cluster_consistency(Node, CheckNodesConsistency) ->
case rpc:call(Node, rabbit_mnesia, node_info, []) of
{badrpc, _Reason} ->
{error, not_found};
{_OTP, _Rabbit, {error, _}} ->
{error, not_found};
{OTP, Rabbit, {ok, Status}} when CheckNodesConsistency ->
case check_consistency(OTP, Rabbit, Node, Status) of
{error, _} = E -> E;
{ok, Res} -> {ok, Res}
end;
{OTP, Rabbit, {ok, Status}} ->
case check_consistency(OTP, Rabbit) of
{error, _} = E -> E;
ok -> {ok, Status}
end;
{_OTP, Rabbit, _Hash, _Status} ->
%% delegate hash checking implies version mismatch
version_error("Rabbit", rabbit_misc:version(), Rabbit)
end.
%%--------------------------------------------------------------------
%% Hooks for `rabbit_node_monitor'
%%--------------------------------------------------------------------
on_node_up(Node) ->
case running_disc_nodes() of
[Node] -> rabbit_log:info("cluster contains disc nodes again~n");
_ -> ok
end.
on_node_down(_Node) ->
case running_disc_nodes() of
[] -> rabbit_log:info("only running disc node went down~n");
_ -> ok
end.
running_disc_nodes() ->
{_AllNodes, DiscNodes, RunningNodes} = cluster_status(status),
ordsets:to_list(ordsets:intersection(ordsets:from_list(DiscNodes),
ordsets:from_list(RunningNodes))).
%%--------------------------------------------------------------------
%% Internal helpers
%%--------------------------------------------------------------------
discover_cluster(Nodes) ->
case lists:foldl(fun (_, {ok, Res}) -> {ok, Res};
(Node, _) -> discover_cluster0(Node)
end, {error, no_nodes_provided}, Nodes) of
{ok, Res} -> Res;
{error, E} -> throw({error, E});
{badrpc, Reason} -> throw({badrpc_multi, Reason, Nodes})
end.
discover_cluster0(Node) when Node == node() ->
{error, cannot_cluster_node_with_itself};
discover_cluster0(Node) ->
rpc:call(Node, rabbit_mnesia, cluster_status_from_mnesia, []).
schema_ok_or_move() ->
case rabbit_table:check_schema_integrity() of
ok ->
ok;
{error, Reason} ->
%% NB: we cannot use rabbit_log here since it may not have been
%% started yet
rabbit_log:warning("schema integrity check failed: ~p~n"
"moving database to backup location "
"and recreating schema from scratch~n",
[Reason]),
ok = move_db(),
ok = create_schema()
end.
%% We only care about disc nodes since ram nodes are supposed to catch
%% up only
create_schema() ->
stop_mnesia(),
rabbit_misc:ensure_ok(mnesia:create_schema([node()]), cannot_create_schema),
start_mnesia(),
ok = rabbit_table:create(),
ensure_schema_integrity(),
ok = rabbit_version:record_desired().
move_db() ->
stop_mnesia(),
MnesiaDir = filename:dirname(dir() ++ "/"),
{{Year, Month, Day}, {Hour, Minute, Second}} = erlang:universaltime(),
BackupDir = rabbit_misc:format(
"~s_~w~2..0w~2..0w~2..0w~2..0w~2..0w",
[MnesiaDir, Year, Month, Day, Hour, Minute, Second]),
case file:rename(MnesiaDir, BackupDir) of
ok ->
%% NB: we cannot use rabbit_log here since it may not have
%% been started yet
rabbit_log:warning("moved database from ~s to ~s~n",
[MnesiaDir, BackupDir]),
ok;
{error, Reason} -> throw({error, {cannot_backup_mnesia,
MnesiaDir, BackupDir, Reason}})
end,
ensure_mnesia_dir(),
start_mnesia(),
ok.
remove_node_if_mnesia_running(Node) ->
case is_running() of
false ->
{error, mnesia_not_running};
true ->
%% Deleting the the schema copy of the node will result in
%% the node being removed from the cluster, with that
%% change being propagated to all nodes
case mnesia:del_table_copy(schema, Node) of
{atomic, ok} ->
rabbit_amqqueue:forget_all_durable(Node),
rabbit_node_monitor:notify_left_cluster(Node),
ok;
{aborted, Reason} ->
{error, {failed_to_remove_node, Node, Reason}}
end
end.
leave_cluster() ->
case nodes_excl_me(cluster_nodes(all)) of
[] -> ok;
AllNodes -> case lists:any(fun leave_cluster/1, AllNodes) of
true -> ok;
false -> e(no_running_cluster_nodes)
end
end.
leave_cluster(Node) ->
case rpc:call(Node,
rabbit_mnesia, remove_node_if_mnesia_running, [node()]) of
ok -> true;
{error, mnesia_not_running} -> false;
{error, Reason} -> throw({error, Reason});
{badrpc, nodedown} -> false
end.
wait_for(Condition) ->
rabbit_log:info("Waiting for ~p...~n", [Condition]),
timer:sleep(1000).
start_mnesia(CheckConsistency) ->
case CheckConsistency of
true -> check_cluster_consistency();
false -> ok
end,
rabbit_misc:ensure_ok(mnesia:start(), cannot_start_mnesia),
ensure_mnesia_running().
start_mnesia() ->
start_mnesia(true).
stop_mnesia() ->
stopped = mnesia:stop(),
ensure_mnesia_not_running().
change_extra_db_nodes(ClusterNodes0, CheckOtherNodes) ->
ClusterNodes = nodes_excl_me(ClusterNodes0),
case {mnesia:change_config(extra_db_nodes, ClusterNodes), ClusterNodes} of
{{ok, []}, [_|_]} when CheckOtherNodes ->
throw({error, {failed_to_cluster_with, ClusterNodes,
"Mnesia could not connect to any nodes."}});
{{ok, Nodes}, _} ->
Nodes
end.
check_consistency(OTP, Rabbit) ->
rabbit_misc:sequence_error(
[check_otp_consistency(OTP),
check_rabbit_consistency(Rabbit)]).
check_consistency(OTP, Rabbit, Node, Status) ->
rabbit_misc:sequence_error(
[check_otp_consistency(OTP),
check_rabbit_consistency(Rabbit),
check_nodes_consistency(Node, Status)]).
check_nodes_consistency(Node, RemoteStatus = {RemoteAllNodes, _, _}) ->
case me_in_nodes(RemoteAllNodes) of
true ->
{ok, RemoteStatus};
false ->
{error, {inconsistent_cluster,
rabbit_misc:format("Node ~p thinks it's clustered "
"with node ~p, but ~p disagrees",
[node(), Node, Node])}}
end.
check_version_consistency(This, Remote, Name) ->
check_version_consistency(This, Remote, Name, fun (A, B) -> A =:= B end).
check_version_consistency(This, Remote, Name, Comp) ->
case Comp(This, Remote) of
true -> ok;
false -> version_error(Name, This, Remote)
end.
version_error(Name, This, Remote) ->
{error, {inconsistent_cluster,
rabbit_misc:format("~s version mismatch: local node is ~s, "
"remote node ~s", [Name, This, Remote])}}.
check_otp_consistency(Remote) ->
check_version_consistency(rabbit_misc:otp_release(), Remote, "OTP").
check_rabbit_consistency(Remote) ->
check_version_consistency(
rabbit_misc:version(), Remote, "Rabbit",
fun rabbit_misc:version_minor_equivalent/2).
%% This is fairly tricky. We want to know if the node is in the state
%% that a `reset' would leave it in. We cannot simply check if the
%% mnesia tables aren't there because restarted RAM nodes won't have
%% tables while still being non-virgin. What we do instead is to
%% check if the mnesia directory is non existant or empty, with the
%% exception of the cluster status files, which will be there thanks to
%% `rabbit_node_monitor:prepare_cluster_status_file/0'.
is_virgin_node() ->
case rabbit_file:list_dir(dir()) of
{error, enoent} ->
true;
{ok, []} ->
true;
{ok, [File1, File2]} ->
lists:usort([dir() ++ "/" ++ File1, dir() ++ "/" ++ File2]) =:=
lists:usort([rabbit_node_monitor:cluster_status_filename(),
rabbit_node_monitor:running_nodes_filename()]);
{ok, _} ->
false
end.
find_auto_cluster_node([]) ->
none;
find_auto_cluster_node([Node | Nodes]) ->
Fail = fun (Fmt, Args) ->
rabbit_log:warning(
"Could not auto-cluster with ~s: " ++ Fmt, [Node | Args]),
find_auto_cluster_node(Nodes)
end,
case rpc:call(Node, rabbit_mnesia, node_info, []) of
{badrpc, _} = Reason -> Fail("~p~n", [Reason]);
%% old delegate hash check
{_OTP, RMQ, _Hash, _} -> Fail("version ~s~n", [RMQ]);
{_OTP, _RMQ, {error, _} = E} -> Fail("~p~n", [E]);
{OTP, RMQ, _} -> case check_consistency(OTP, RMQ) of
{error, _} -> Fail("versions ~p~n",
[{OTP, RMQ}]);
ok -> {ok, Node}
end
end.
is_only_clustered_disc_node() ->
node_type() =:= disc andalso is_clustered() andalso
cluster_nodes(disc) =:= [node()].
me_in_nodes(Nodes) -> lists:member(node(), Nodes).
nodes_incl_me(Nodes) -> lists:usort([node()|Nodes]).
nodes_excl_me(Nodes) -> Nodes -- [node()].
e(Tag) -> throw({error, {Tag, error_description(Tag)}}).
error_description({invalid_cluster_node_names, BadNames}) ->
"In the 'cluster_nodes' configuration key, the following node names "
"are invalid: " ++ lists:flatten(io_lib:format("~p", [BadNames]));
error_description({invalid_cluster_node_type, BadType}) ->
"In the 'cluster_nodes' configuration key, the node type is invalid "
"(expected 'disc' or 'ram'): " ++
lists:flatten(io_lib:format("~p", [BadType]));
error_description(cluster_node_type_mandatory) ->
"The 'cluster_nodes' configuration key must indicate the node type: "
"either {[...], disc} or {[...], ram}";
error_description(invalid_cluster_nodes_conf) ->
"The 'cluster_nodes' configuration key is invalid, it must be of the "
"form {[Nodes], Type}, where Nodes is a list of node names and "
"Type is either 'disc' or 'ram'";
error_description(clustering_only_disc_node) ->
"You cannot cluster a node if it is the only disc node in its existing "
" cluster. If new nodes joined while this node was offline, use "
"'update_cluster_nodes' to add them manually.";
error_description(resetting_only_disc_node) ->
"You cannot reset a node when it is the only disc node in a cluster. "
"Please convert another node of the cluster to a disc node first.";
error_description(not_clustered) ->
"Non-clustered nodes can only be disc nodes.";
error_description(no_online_cluster_nodes) ->
"Could not find any online cluster nodes. If the cluster has changed, "
"you can use the 'update_cluster_nodes' command.";
error_description(inconsistent_cluster) ->
"The nodes provided do not have this node as part of the cluster.";
error_description(not_a_cluster_node) ->
"The node selected is not in the cluster.";
error_description(online_node_offline_flag) ->
"You set the --offline flag, which is used to remove nodes remotely from "
"offline nodes, but this node is online.";
error_description(offline_node_no_offline_flag) ->
"You are trying to remove a node from an offline node. That is dangerous, "
"but can be done with the --offline flag. Please consult the manual "
"for rabbitmqctl for more information.";
error_description(removing_node_from_offline_node) ->
"To remove a node remotely from an offline node, the node you are removing "
"from must be a disc node and all the other nodes must be offline.";
error_description(no_running_cluster_nodes) ->
"You cannot leave a cluster if no online nodes are present.".
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