PowerScale: Impact of Daylight Saving Time changes in Egypt on OneFS

This affects clusters that use EET Africa/Cairo time zone. 
The Egyptian government reintroduces DST starting on 28th April until 27th October 2023.

Current OneFS versions do not take the Daylight Savings Time changes into account there is but a workaround that can be implemented on all versions.

There is no impact to cluster operations as a result of the change and the impact is cosmetic in nature where:

• The cluster displays an incorrect time in the CLI command outputs and logs
• The Schedule-based jobs "SIQ, job engine,… And so on" are not aligned with scheduling expectations. For example: A SyncIQ job that is scheduled to run on 2:00 PM will run one hour earlier after 28th of April 2023.
• WebUI displays incorrect timestamps. 

Some applications have strict requirements for accurate time zone reporting. 

Ensure that the DST change is applied using the workaround in this article.

A DST change was recently introduced in Egypt. 
Current OneFS versions do not take the Daylight Savings Time changes into account.

Engineering will include the necessary change in a future OneFS release.

The workaround below updates the EET time zone records. It should be performed on a OneFS cluster node as the root user.

The workaround does not fix the WebUI timestamp display.

Workaround procedure
1) Connect to any node by SSH and login using root user.
2) Confirm that EET (Africa/Cairo) is the cluster time zone:

# cat /etc/ifs/array.xml| grep -i time
  <timezone>Africa/Cairo</timezone>

3) If it is not using the EET (Africa/Cairo) time zone, this article does not apply to your cluster.
4) If it is using EET, run the following command to examine the current settings before changing them.
The command should not return any output:

# zdump -v /usr/share/zoneinfo/Africa/Cairo | grep 2023
#

5) Download the new time zone files to your cluster in the new time zone folder. 
This file should be downloaded to ~/timezone.

The command below fetches the time zone files over the Internet directly from the cluster.
Note: If your cluster does not have direct WAN or Internet access, download this file on your personal computer then upload it to the cluster to ~/timezone.

# mkdir ~/timezone
# cd ~/timezone/
# wget https://data.iana.org/time-zones/releases/tzdata2023b.tar.gz --no-check-certificate
# tar -zxvf tzdata2023b.tar.gz

6) Run the following command to create the new time zone package.
Note: The first command verifies that the time zone files are intact. If the command does not return an output, contact Dell Support for assistance.

# for m in AX BL BQ CW GG IM JE ME MF RS SS SX ; do echo -n $m: ; grep -c ^$m /usr/share/misc/iso3166 ; done
# zic -d zoneinfo -p Africa/Cairo -m 444 -y yearistype.sh africa

7) Back up, and then replace the existing time zone files.

# mkdir -p /ifs/data/tz_bak
# mkdir -p /ifs/data/tz_new
# cp -R /usr/share/zoneinfo /ifs/data/tz_bak/
# cp -R ~/timezone/zoneinfo /ifs/data/tz_new/

8) Replace the time zone files for all nodes cluster-wide and override old files.

# isi_for_array -s 'cp -Rf /ifs/data/tz_new/zoneinfo/* /usr/share/zoneinfo'

9) Check the new time zone. It should show the expected DST changes as below.

# zdump -v /usr/share/zoneinfo/Africa/Cairo | grep 2023
/usr/share/zoneinfo/Africa/Cairo  Thu Apr 27 21:59:59 2023 UTC = Thu Apr 27 23:59:59 2023 EET isdst=0 gmtoff=7200
/usr/share/zoneinfo/Africa/Cairo  Thu Apr 27 22:00:00 2023 UTC = Fri Apr 28 01:00:00 2023 EEST isdst=1 gmtoff=10800
/usr/share/zoneinfo/Africa/Cairo  Thu Oct 26 20:59:59 2023 UTC = Thu Oct 26 23:59:59 2023 EEST isdst=1 gmtoff=10800
/usr/share/zoneinfo/Africa/Cairo  Thu Oct 26 21:00:00 2023 UTC = Thu Oct 26 23:00:00 2023 EET isdst=0 gmtoff=7200

10) Confirm that the date command returns the correct time.

isi_for_array -s date