Technical Blog Post
Abstract
Don't limit your inbound or outbound sessions to 6 in Connect:Direct for z/OS. Review the default values for MAXPRIMARY, MAXSECONDARY, and MAXPROCESS.
Body
Do you have MAXPRIMARY, MAXSECONDARY, and MAXPROCESS coded in your Init Parms? The default values may not give you the number of sessions you want.
Default values are as follows:
MAXPRIMARY = 6
MAXSECONDARY = 6
MAXPROCESS = MAXPRIMARY + MAXSECONDARY
With these default values, you will never get more than 6 inbound and 6 outbound sessions at once.
If you see one of these messages in your joblog, you have hit the max on these values:
Message STAA005I is for MAXSECONDARY.
Message STAA006I is for MAXPRIMARY.
Message STAA010I is for MAXPROCESS.
Note that if you are the SNODE and these limits are hit on the PNODE side, you may see this as a communications failure.
Best Practice recommendation: Code these Init Parms according to your needs.
MAXPROCESS = xx – where xx is your licensed number of sessions which will keep you from exceeding your licensed value. If you have the X01 unrestricted license, choose a suitable value.
Now the MAXSECONDARY and MAXPRIMARY can be adjusted.
Usually you want to set these values less than the MAXPROCESS but the values can add up to more than the MAXPROCESS, since MAXPROCESS is the absolute limit of the number of sessions. They do not have to be evenly divided.
For example, you want no more than 15 sessions, you might have the following:
MAXPROCESS = 15
MAXSECONDARY = 10
MAXPRIMARY = 10
This means that the total sessions will never be more than 15. (Based on MAXPROCESS)
The secondary and primary sessions can be no more than 10 each.
If secondary has 10 sessions at one time, then that still leaves at least 5 for primary and vice versa. We do not recommend setting those values to the MAXPROCESS value because that could lock out secondary or primary from starting if you happen to get 15 of one type.
Note: Before adjusting the number of sessions allowed for Connect:Direct for z/OS, you should understand which type of license you have. You must always conform to any license restrictions on the number of sessions permitted (if one applies). If your license refers to 'Standard Edition' or X09, then you have a restricted number of concurrent sessions. If you have X01, then there is no session restriction.
Additional information can be found here:
blog entry Connect:Direct for z/OS: Restricted Concurrent Sessions
System Administration Guide
MAXPRIMARY = number of PNODE sessions
MAXSECONDARY = number of SNODE sessions
MAXPROCESS = number of executing PNODE and SNODE Processes
Technote 1654902 "5655-X01 and 5655-X09: Differences between Sterling Connect:Direct for z/OS Program Numbers."
UID
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