I think I failed to mention we are running NTP and the servers where they are doing subtraction of timestamps to get deadlines are all zLinux. Without NTP things fall apart quickly here. Maybe things are being steered at the same rate? Or it's off so much at boot time due to the leap seconds that it takes a long time to get in sync?
-----Original Message----- From: Linux on 390 Port [mailto:[email protected]] On Behalf Of Robert J Brenneman Sent: Monday, July 25, 2016 12:04 PM To: [email protected] Subject: Re: [LINUX-390] Back to the future? In a heterogeneous environment if your non Z NTP systems are off by roughly 26 seconds compared to your STP managed Z Linux clocks it could be due to this: https://access.redhat.com/articles/15145 basically - the default Linux timezone files do not respect leap seconds, but the long time mainframe operator does and sets up STP correctly. The fix is to either 1) run NTP on Linux on Z and steer it away from the STP time ( bleh!) 2) or run NTP on the non-Z Linux systems against an NTP server running on Linux on Z ( hacky and gross ) 3) or to tell the non-Z linux systems to account for leap seconds by using the 'right' zonefiles: cp /usr/share/zoneinfo/right/America/Los_Angeles /etc/localtime be aware that (3) will probably break stuff if you make that setting while applications are running. It is probably best to shut all applications down, make the change, reboot, and then start applications back up. Test, Test more, and Test again. Additionally - you should probably not use those 'right' zonefiles on a Linux on Z environment under STP clocking since you don't want to account for leap seconds twice. That would probably be bad. -- Jay Brenneman ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/
