dslreports logo
 
    All Forums Hot Topics Gallery
spc
uniqs
23

exocet_cm
Writing
Premium Member
join:2003-03-23
Brooklyn, NY

exocet_cm to batsona

Premium Member

to batsona

Re: ESXi 5.0 Question: NTP....

said by batsona:

OP Here: I think I got it. The way ESXi deals with its time is weird & confusing. The time you see thru the VSphere Client is translated to the local time of that VSphere client. In my case this is eastern time, or GMT-5 (not the 4hr difference I saw earlier in this thread -- I can't count..) So let's say:

eastern time: 13:00
UTC: 18:00 (the time I set for the ESX server via the VSphere client)

My guest OS would boot up & its time would be 23:00

So, I set "13:00" as the current time on my ESXi server, via the VSphere client. (weird, I noticed when I did this, the time turned from red to black). NTP didn't yell at me at all when I set the time to something different than what it was hearing via NTP, but maybe the color of the time was telling me something.

With my ESXi time set to 13:00, I rebooted my guest, and sure enough I now have correct UTC on the guest (18:00) Setting the time-sync to on vs. off in the "VMware Tools" section of the properties didn't do anything to affect what was going on during boot. BUT: I have a question:

If the time-sync with the guest is turned on, does that mean the guest OS will receive a time-sync thru VMware-Tools, a la NTP? if so, I don't want that. I do understand that the OS (windows, mac, Linux....) will receive a time-sync upon boot, because the OS will look to the HW clock to set its own. However, once the OS is up, I'd like ESXi to NOT communicate time to the guest; and I'd like it set purely via 'ntpdate' in Linux (run by root's Cron)

I'm not very familiar with the sync time option in the guest settings. I personally don't use it because all of my guest VMs that require NTP are Windows-based machines and I sync them with my LAN's NTP server. My Linux VMs are for testing various things and time synchronization isn't an issue.

Have a read of the VMware KB article that I posted about Linux distro time synchronization whenever you have a spare hour.
batsona
Maryland
join:2004-04-17
Ellicott City, MD

1 recommendation

batsona

Member

OP: Problem solved.. The documentation should print wording in bold letters to the effect: When setting ESXi time via the VSphere client, make sure you use the local time in your time-zone, even if you want to use UTC throughout your environment. If local time is 13:00 and UTC is 18:00, tell the ESXi server that it's 13:00, and you'll be fine.
gavindcht
join:2013-03-31

gavindcht to exocet_cm

Member

to exocet_cm
So just to verify, the Server and client must have the same time set?