IBM Support

DFHCF0443 CF structure request failed opening file - increasing MAXTABLES

Question & Answer


Question

I have created a coupling facility data table (CFDT) for the DFHBRNSF file that is pointing to the same structure where the CFDT for CICSPlex SM (CPSM) Optimized workload resides. The structure was created with MAXTABLES=1 specified. So, now when I try to open the DFHBRNSF file, it fails with the following message:

DFHCF0443 CF structure strname request failed, all lists are in use.

I tried to change MAXTABLES=4 but I am still receiving message DFHCF0443. How can I increase MAXTABLES for this structure?

Also, is it okay to share the same structure server together?

Answer

If the number of data lists specified using the MAXQUEUES or MAXTABLES server parameter is too small, an attempt to allocate a new data list will fail with message DFHXQ0443 or message DFHCF0443.

The MAXTABLES variable will only take effect when a CF structure is being created. The MAXTABLES parameter specifies the maximum number of data lists to be reserved when the CF structure is allocated, and determines the maximum number of tables that can be stored in the structure. This parameter also determines how many list headers are defined when the CF structure is created.

Topic Increasing the number of data lists in the CICS Transaction Server for z/OS (CICS TS) V5.3 documentation states:

There is no way to increase the number of lists without deleting and recreating the structure, which necessitates closing down all of the servers temporarily. You cannot use system-managed rebuild to increase the number of data lists because it copies this number from the existing structure.

You can preserve existing data by using the server program to unload it to a sequential file, and then using SETXCF FORCE to delete the existing structure. You can then use the server program again to reload the data, and allocate a new structure with the appropriate MAXQUEUES or MAXTABLES parameter.

This topic can be found under Managing the pool structure.

In regards to sharing the CF structure between the CPSM CFDT and the file, it really depends on how busy your dynamic routing environment is. The reason there is a region status (RS) server is to keep it isolated from the application CFDT server. If the RS server is bogged down handling application requests, then it could slow down the dynamic routing environment.

It is your choice to share the CF structure but IBM does do not recommend it.

Cheers,
Shayla Robinson
CICS/CPSM Level 2 Support

[{"Business Unit":{"code":"BU011","label":"Systems - zSystems software"},"Product":{"code":"SSGMGV","label":"CICS Transaction Server"},"Platform":[{"code":"PF035","label":"z\/OS"}],"Component":"File Control","Version":""}]

Product Synonym

CICS/TS CICSTS CICS TS CICS Transaction Server

Document Information

Modified date:
01 November 2017

UID

dwa1410391