With the availability of z/OS 3.1 on 9/29/2023, the ‘D ETR’ command has been
enhanced to display the coordinated timing network (CTN) configuration. Previously, this
information was only viewable via the HMC ‘Manage System Time’ panel.
A new IEA399I message is issued in response to the ‘D ETR,CTN’ command to the issuing
console (EMCS, S(MCS), or SYSCONS). Additionally, the IEA399I message is issued to hardcopy
during z/OS system IPL and whenever there is a CTN configuration change.
In our test environment, we issued the ‘D ETR,CTN’ command and ensured it matched the
information on the HMC ‘Manage System Time’ panel for various configurations. We also
ensured hardcopy only messages were issued during z/OS IPLs and for multiple different CTN
role changes.
Here’s the ‘D ETR,CTN’ command issued from EMCS console:
And the corresponding view in HMC Manage System Time:
We see an IEA399I message issued to hardcopy (OPERLOG) at z/OS IPL:
(From HCL mapping, MESSAGE WAS ISSUED AS HARDCOPY ONLY - Offset x’2E’; Byte 3, the x’02’ flag)
The HMC view after CTN role change:
And an IEA399I message issued to hardcopy (OPERLOG) with CTN role change:
(From HCL mapping, MESSAGE WAS ISSUED AS HARDCOPY ONLY - Offset x’2E’; Byte 3, the x’02’ flag)
This new message can give useful information about the CTN configuration in terms of roles, whether in response to the new ‘D ETR,CTN’ command option, for quick confirmation of changes in the CTN as you make them, or for historical purposes in your z/OS syslog or operlog whenever you IPL. It provides this information concisely and quickly without having to log into the HMC or derive it from other z/OS messages.
More zPET blogs with our experiences and troubleshooting with STP CTN can be found here: