Changing time

qwertys21 · ‎10-26-2007

As we are changing the clock in the UK, how can I check if the UK Switches will automatically change time?

We have the switches pointing to NTP Servers

Richard Burts · ‎10-26-2007

Ade

It certainly is best practice to have your switches pointing to NTP servers. This assures that they will learn accurate time.

But using NTP does not have anything to do with changing the clock. NTP communicates time as UTC (used to be called GMT) into all time zones without any allowance for local time zone or offset to daylight savings. It is up to the local device to offset from UTC to derive the local time.

The IOS has a configuration option to make the offset for local time zone (the clock timezone command) and a configuration option for daylight savings (the clock summer-time command). If you want to check whether your switches will automatically change time then do show clock detail. (adding the detail parameter will cause the switch to show when it will change time for summer/daylight savings).

HTH

Rick

HTH

Rick

Kevin Dorrell · ‎10-26-2007

Do this config and it will all be automatic:

clock timezone GMT 0

clock summer-time BST recurring last Sun Mar 2:00 last Sun Oct 3:00

Kevin Dorrell

Luxembourg

qwertys21 · ‎10-26-2007

Thanks

SO if I do a

sh clock

16:49:20.602 BST Fri Oct 26 2007

This shows that the BST time ise set?

Thanks

Richard Burts · ‎10-26-2007

Ade

The show clock command as you have it here will simply show what time the switch believes that it is (with whatever offsets have been configured) and does not tell you whether (or when) it will change the clock for daylight savings. To see the additional information try using the "show clock detail" command.

HTH

Rick

HTH

Rick

Kevin Dorrell · ‎10-26-2007

Be careful, you would get the same result with

clock timezone BST 1

... until the early hours of Sunday morning ...

Kevin Dorrell

Luxembourg