Distributed publish/subscribe system queues
Four system queues are used by queue managers for publish/subscribe messaging. You need to be aware of their existence only for problem determination and capacity planning purposes.
See Balancing producers and consumers in publish/subscribe networks for guidance on how to monitor these queues.| System queue | Purpose |
|---|---|
| SYSTEM.INTER.QMGR.CONTROL | IBM MQ distributed publish/subscribe control queue |
| SYSTEM.INTER.QMGR.FANREQ | IBM MQ distributed publish/subscribe internal proxy subscription fan-out process input queue |
| SYSTEM.INTER.QMGR.PUBS | IBM MQ distributed publish/subscribe publications |
| SYSTEM.HIERARCHY.STATE | IBM MQ distributed publish/subscribe hierarchy relationship state |
On z/OS, you set up the necessary system objects when you create the queue manager, by including the CSQ4INSX, CSQ4INSR and CSQ4INSG samples in the CSQINP2 initialization input data set. For more information, see Task 13: Customize the initialization input data sets.
The attributes of the publish/subscribe system queues are shown in Table 2.| Attribute | Default value |
|---|---|
| DEFPSIST | Yes |
| DEFSOPT | EXC |
| MAXMSGL |
On Multiplatforms: The value of the MAXMSGL parameter of the ALTER QMGR command On z/OS: 104857600 (that is, 100 MB) |
| MAXDEPTH | 999999999 |
| SHARE | N/A |
| STGCLASS |
This attribute is used only on z/OS platforms |
- Distributed publish/subscribe system queue errors
Errors can occur when distributed publish/subscribe queue manager queues are unavailable. This affects the propagation of subscription knowledge across the publish/subscribe network, and publication to subscriptions on remote queue managers.
Parent topic: Plan for distributed publish/subscribe network
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