Exadata OEL6 to OEL7 upgrade. DB TimeZone issue

Hello all.

After upgrading OS on Exadata dbnodes from OEL6 to OEL7, all corresponding databases started with UTC time zone and "local" timezone was ignored.

[root@hostname~]# timedatectl
      Local time: Wed 2021-03-03 12:46:04 PST
  Universal time: Wed 2021-03-03 20:46:04 UTC
        RTC time: Wed 2021-03-03 20:46:02
       Time zone: America/Los_Angeles (PST, -0800)
     NTP enabled: yes
NTP synchronized: yes
 RTC in local TZ: no
      DST active: no
 Last DST change: DST ended at
                  Sun 2020-11-01 01:59:59 PDT
                  Sun 2020-11-01 01:00:00 PST
 Next DST change: DST begins (the clock jumps one hour forward) at
                  Sun 2021-03-14 01:59:59 PST