Figured I'd give it a quick google for this weirdness and stumbled upon this report. Confirmed it, but then started doubting if it actually is cron that's causing this weirdness. So I put a simple strace on my freshly restarted cron with strace -f -p <pid> -s 1000 2>&1 | grep 'CRON\[' and left this running for half a day. Guess what? You can see cron logging like it should, no jumping around. But then when I look at the actual syslog again, I see the cron entries jumping around... So that makes one question syslog somehow... No time yet to dive into that though...
-- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to cron in Ubuntu. https://bugs.launchpad.net/bugs/1429427 Title: Unexplainable time jumps in CRON Status in cron package in Ubuntu: Confirmed Bug description: On my main server I see unexplainable time jumps backwards in the syslog. Those jumps affect CRON. Example: Feb 10 06:48:01 nostromo CRON[20351]: (root) CMD ( /storage/exec/checkinternet.sh 2>/dev/null 1>/dev/null) Feb 10 06:49:01 nostromo CRON[20364]: (root) CMD ( /storage/exec/checkinternet.sh 2>/dev/null 1>/dev/null) Feb 10 06:50:01 nostromo CRON[20386]: (root) CMD ( /storage/exec/status-nostromo.sh >/dev/null 2>&1) Feb 7 05:40:01 nostromo CRON[20389]: (root) CMD ( /storage/exec/checkinternet.sh 2>/dev/null 1>/dev/null) Feb 10 06:50:01 nostromo CRON[20390]: (root) CMD ( /storage/exec/checkinternet.sh 2>/dev/null 1>/dev/null) Feb 10 06:50:01 nostromo CRON[20391]: (root) CMD ( /storage/exec/checkip.sh 2>/dev/null 1>/dev/null) For debugging I did the following: Start xclock and watch xclock and tail -f /var/log/syslog in parallel. When CRON logged a wrong time, xclock did NOT show any time jump but seemed to freeze for a fraction of a second. Open a screen and start a script that will once per second read the time (in unix seconds) and compare the read time with the time read a second ago. If the current time was smaller, the script would send an email with a process list from before and after the jump. The script also never detected any time jump. In summary, my current impression is that there might be a bug in CRON because no other programm seems to be able to see the "wrong" time. The server in question is syslog server for 4 servers and 3 network devices. The time jumps exclusively show in syslog entries from the local CRON instance. Not in any remote syslog entry and not in any other local syslog entry, e.g. from DHCPD, bind, tftpd, etc. etc. Also, after a reboot, things work ok for several days upto about 2 or 3 weeks. Then the "time jumps" start to occur with increasing frequency. I don't use user crontabs but maintain all jobs in /etc/crontab. I have number of jobs which are triggered every minute and another number of jobs which are triggered every 5 minutes (maybe some CRON internal counter overflow problem?). Hardware: Asus P9D-V Intel Xeon E3-1240L V3 16GB ECC RAM 128GB SSD System 3x3TB ZFS RaidZ2 storage 1x3TB Misc. data CMOS battery already changed and board inspected. nostromo:~ # lsb_release -rd Description: Ubuntu 14.04.2 LTS Release: 14.04 nostromo:~ # apt-cache policy cron cron: Installed: 3.0pl1-124ubuntu2 Candidate: 3.0pl1-124ubuntu2 Version table: *** 3.0pl1-124ubuntu2 0 500 http://us.archive.ubuntu.com/ubuntu/ trusty/main amd64 Packages 100 /var/lib/dpkg/status To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/cron/+bug/1429427/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
