My public facing workstation is running CentOS 6.8. For some time now I have had a couple of VMs running in the background, one at C7 and one running Fedora 23. Each evening when I shut down the workstation it suspends the VMs, and in the morning they restart happily enough. However after the Christmas/New Year break I realised that time had slipped backwards several weeks on the VMs. I narrowed it down to NTP failing, which in turn was due to the host's firewall. I duly opened the port and all seemed fine until the following morning when time had slipped back half a day again. The client NTP daemons were showing zero for the
reach and a hyphen for the
when. Even after a couple of hours (
poll had got up to 1024 by this stage) they hadn't resynced. I manually restarted them, but the following day the same scenario presented itself. I've now modified
ntp.conf as follows:
Code: Select all
...
server 192.168.122.1 minpoll 3 maxpoll 6
...
# Allow for large steps when the host is shutdown or rebooted.
#
tinker panic 0
This morning both had frozen time overnight. The update job contains
ssh <name> date,
ssh <name> yum -y update (dnf for the F23 VM) and
ssh <name> sync ; sync. Even after the update NTP was still frozen. When I ssh'ed in interactively (about 20 minutes after bootup) NTP on the C7 VM then started reaching the host, and in due course jumped back to the present; the Fedora machine also started reaching the hist, but refused to sync and needed a daemon restart.
All three machines (host + clients) are updated daily.
This is a test/development machine, not a server, so the priority is low, more of an annoyance. Does anyone have any ideas on kicking NTP on the VMs into life? Is there a way to make the F23 VM jump when time changes significantly?
Thanks,
Martin