Reserved Topics

Solace PubSub+ uses a number of reserved topics to implement some specific messaging features. Each of these topic subscriptions begin with the # character, which is then followed by a specific, reserved sequence of characters. Some special topics only use a reserved string for the first hierarchical level of the topic subscription, others may reserve more than one level.

Any topic starting with # is reserved for special topics. Topics defined by applications must not start with #. As an exception to this rule—with request/reply across multi-node routing networks, where a subscription propagation delay may occur—topics of the form #P2P/v:routerName/<something> can be used.

Reserved Topic Subscriptions

Topic Subscription

Published Topics That Match the Subscription

Description

#LOG/...

#LOG/level/SYSTEM/hostName/event/Name

#LOG/level/VPN/hostName/eventName/vpnName[/suffix]

#LOG/level/CLIENT/hostName/eventName/vpnName/clientName

#LOG/level/APPLICATION/hostName/eventName/vpnName[/suffix]

#LOG/INFO/SUB_ADD/subscribedTopic

#LOG/INFO/SUB_DEL/subscribedTopic

Used by the event broker to publish events to the message bus.

Published by: event broker

Subscribed to by: management client applications

#MCAST/>

#MCAST/CACHEMGR

Used by PubSub+ Cache instances to broadcast initial messages to find their Cache Manager.

Published by: PubSub+ Cache Instances

Subscribed to by: event broker

#noexport/#share/ShareName/topicFilter

#noexport/topicFilter

#noexport/#share/ShareName/topicFilter

#noexport/topicFilter

Any subscription (shared or non-shared) that starts with #noexport is not advertised by the local node (through MNR/DMR) to other nodes in the network. This prevents published messages on those remote nodes from being attracted to the subscriber on the local node.

If the subscription is qualified with #noexport then it only attracts messages published locally on the same broker where the subscriber is. It will not be advertised by MNR/DMR. An individual subscription can be flagged #noexport, even if the subscriptions of the message VPN as a whole are being exported.

#noexport/#share/ShareName/topicFilter is used to specify a non-exported shared subscription, where ShareName is the shared subscription identifier, and topicFilter is the topic filter.

#noexport/topicFilter allows applications to receive messages matching a topicFilter that are received by the node the client is connected to by not exporting the subscription to other nodes in a routed (DMR or MNR) network.

#noexport applies only to subscriptions and is unsupported for cache requests.

Published by: client applications

Subscribed to by: client applications

#P2P/CACHEINST/distibutedCacheName

Used to direct PubSub+ Cache requests to a distributed cache.

Published by: client applications

Subscribed to by: PubSub+ Cache Distributed Cache

#P2P/CACHEINST/cacheClusterName

Used to direct PubSub+ Cache requests to a cluster in a distributed cache.

Published by: client applications

Subscribed to by: PubSub+ Cache Cache Cluster

#P2P/CACHEINST/cacheInstanceName

Used to direct PubSub+ Cache requests to a specific cache instance in a distributed cache.

Published by: client applications

Subscribed to by: PubSub+ Cache

#P2P/routerName/clientUsernameHash/#client/>

#P2P/routerName/clientUsernameHash/#client/CACHEMGR

Used by PubSub+ Cache instances to communicate with their Cache Manager.

Published by: PubSub+ Cache

Subscribed to by: event broker

#P2P/routerName/#client/>

#P2P/routerName/#client/CACHEMGR

Used by PubSub+ Cache instances to communicate with their Cache Manager.

Published by: PubSub+ Cache Instances

Subscribed to by: event broker

#P2P/v:routerName/clientUsernameHash/clientName/>

#P2P/v:routerName/clientUsernameHash/clientName/...

Used for Direct Messaging request/reply. The name space is controlled by the client API, but the event broker sets the prefix.

Published by: client applications

Subscribed to by: client API

#P2P/v:routerName/clientName/>

#P2P/v:routerName/clientName/...

Used for Direct Messaging request/reply. The name space is controlled by the client API, but the event broker sets the prefix.

This pattern is used by client connections in SolOS 8.2 and below.

Published by: client applications

Subscribed to by: client API

#P2P/QUE/queueName

Subscriptions that allow clients to publish messages to and/or consume messages from the specified durable queues.

Published by: client applications

Subscribed to by: client applications

#P2P/QTMP/v:routerName/queueName

Subscriptions that allow clients to publish messages to and/or consume messages from the specified non-durable queues. The client App/Mgmt controls the name space, but the event broker sets the prefix.

Published by: client applications

Subscribed to by: client applications

#P2P/TTMP/v:routerName/tempTopic

Used for temporary topics. Name space is controlled by the client API, but the event broker sets the prefix.

Published by: client applications

Subscribed to by: client applications

#P2P/v:routerName/>

#P2P/v:routerName/...

Subscription created when a virtual router is discovered, to attract #P2P traffic for the event broker. This subscription is not visible in CLI.

Published by: client applications

Subscribed to by: event broker

#P2P/routerName/>

#P2P/routerName/...

Subscription always created when a physical event broker is discovered, to attract #P2P traffic for the event broker. This subscription is not visible in CLI.

Published by: client applications

Subscribed to by: event broker

#SEMP/routerName/>

#SEMP/routerName/SHOW

#SEMP/routerName//ADMIN/CLIENT

#SEMP/routerName/ADMIN/DISTRIBUTED-CACHE

Used to direct SEMP commands to a physical event broker name.

Published by: client applications

Subscribed to by: event broker

#SEMP/v:routerName/>

#SEMP/v:routerName/SHOW

#SEMP/v:routerName//ADMIN/CLIENT

#SEMP/v:routerName/ADMIN/DISTRIBUTED-CACHE

Used to direct SEMP commands to a virtual router name. Subscription is only present when a given event broker is active for the virtual router name.

Published by: client applications

Subscribed to by: event broker

#share/ShareName/topicFilter

A Direct Messaging feature to load balance data amongst clients.

A shared subscription has the form: #share/ShareName/topicFilter, where ShareName is the shared subscription identifier, and topicFilter is the topic filter.

Published by: client applications

Subscribed to by: client applications

#insights/...

#insights/pinger/ping

Used to check inter-broker connectivity by PubSub+ Cloud.

Published by: PubSub+ Insights client

Subscribed to by: PubSub+ Insights client

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