Overview

If daylight saving time starts soon, you may wonder if any adjustment or configuration is needed to prepare for it.

Information

To determine if the servers are already configured for the start of daylight saving time, check the servers and see if the /etc/localtime/ file already contains the required changes. You can do that by running the following command on every node (replace YYYY with the year you want information for):

zdump -v /etc/localtime |grep YYYY

You can expect a result similar to this:

[root@nmm-asu-mgr ~]# zdump -v /etc/localtime |grep 2021
zdump: warning: zone "/etc/localtime" abbreviation "-04" lacks alphabetic at start
/etc/localtime  Sun Mar 28 02:59:59 2021 UTC = Sat Mar 27 23:59:59 2021 -03 isdst=1 gmtoff=-10800
/etc/localtime  Sun Mar 28 03:00:00 2021 UTC = Sat Mar 27 23:00:00 2021 -04 isdst=0 gmtoff=-14400
/etc/localtime  Sun Oct  3 03:59:59 2021 UTC = Sat Oct  2 23:59:59 2021 -04 isdst=0 gmtoff=-14400
/etc/localtime  Sun Oct  3 04:00:00 2021 UTC = Sun Oct  3 01:00:00 2021 -03 isdst=1 gmtoff=-10800
[root@nmm-asu-mgr ~]#

In the above example, servers have been configured such that Daylight Saving Time for 2021 is in force till March 27 at Local Time 23:59:59, after which time will revert to regular (non-DST) hours. Daylight Saving Time commences again on October 2 at Local Time 23:59:59. 

Please check the results for every node by running the same command viz. zdump -v /etc/localtime |grep YYYY(replace YYYY with specific year). If the next period is already configured correctly, there is nothing to do on the SMSC side. The servers are ready to automatically change their time on the date/time required.

If you find that DST has not been configured correctly or is missing, please contact Newnet support.