Time Zones and Best Practices

[Scott Hanson]

All,

If I have several sites across the country but the HQ is on EST what is the recommended practice to configure the time zones on the network equipment in different time zones.  Should it be configured to match the local time zone or the time zone of the HQ?  In this case the HQ is where all the management of the network equipment is performed.  I can see an argument for both ways

Thanks in advance!  All replies rated.

[Joseph W. Doherty]

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I suggest using UCT.

[Richard Burts]

As I read the original post it seems the question is whether to have the time zone of network equipment reflect the local environment or whether they should all be set with a common value. I believe that the response from Joseph indicates a common setting and further advocates not setting a time zone but using the default Universal Coordinated Time.

Before I give a response I believe that there are a couple of questions we should look at before we make a decision. In particular we need to understand whether there are any things in the configuration that are time sensitive, such as time based access list, or perhaps EEM scripts that might trigger based on time. In that case matching the local environment is preferable.

I note that the original post tells us that all management of the network devices is done from HQ. I believe that this is an important qualification and in this case I agree with Joseph that setting to a common time zone is preferable. It could be especially helpful in situations where you are investigating an issue and are comparing logs from multiple devices in multiple time zones to have a common version of what time the event occurred. That is also a point that emphasizes the importance of using NTP to set the time.

HTH

Rick

[Leo Laohoo]

Depends on who's doing the monitoring. 

If you're using EST at HQ and you've got routers on the PST zone, why bother doing two (or more) timezones.  Settle to a timezone where it's easy to determine the exact time of the event and no need to convert.  

The main thing is to ensure the appliance's clock source is set accurately.  Make sure the logging event has the correct time/date/year setting.  

I have seen a lot of "sh logs" where network admin were just too "irresponsible" to realize how important the second and third lines of any configurations are.