[Edgecore SONiC] NTP (Network Time Protocol) Follow

Reference model:

• Switch model name:

- AS7726-32X

- AS7326-56X

- AS7816-64X

- AS5835-54X(T)

- AS4630-54PE

- AS9716-32D

- AS8000(Minipack)

- Wedge100BF-32X

• Edgecore SONiC version: 

- Edgecore-SONiC_20201123_130028_ec202006_74

- Edgecore-SONiC_20201229_070315_ec202006_101

- Edgecore-SONiC_20201229_070315_ec202006_bfn_65(Wedge100BF-32X)

Restriction:

1. NTP command only supports IP address, not URL.
2. If management IP get from DHCP server, NTP won't work well to sync with the remote NTP server. SONiC will request the NTP service by loopback interface

Example: Sync the time with remote NTP server.

Procedure: 

Step 1.  Configure IP address to network communication (Refer to Management and front port IPv4/IPv6 Address)

Step 2. Add the NTP server via the command line.

admin@sonic:~$ sudo config ntp add 216.239.35.12

Caution: Since Restriction #1, we cannot set the URL via the command line. But we can set the URL via editing config_db.json.

admin@sonic:/etc/sonic$ sudo vi config_db.json
{
    ...omitted
    "NTP_SERVER": {
        "1.debian.pool.ntp.org": {},
        "time.google.com": {},
        "216.239.35.12": {}
    },
    ...omitted
}

Apply the config_db.json.

admin@sonic:~$ sudo config reload -y

Add the DNS server. (Refer to this article)

admin@sonic:~$ sudo vi /etc/resolv.conf     
nameserver 8.8.8.8 

Step 3. Save the setting to config_db.json

admin@sonic:~$ sudo config save -y

Step 4-1. List all the timezone information.

admin@sonic:~$ sudo timedatectl list-timezones

Note: Use arrow key to roll up and down, press "Space" for next page, "q" for quit.

Step 4-2. Modify to your timezone.

admin@sonic:~$ sudo timedatectl set-timezone Asia/Taipei

Step 5. Check the system time by linux command

admin@sonic:~$ date
Thu 31 Dec 2020 02:48:24 PM CST

Step 6. Check NTP status

admin@sonic:~$ date 
Thu 31 Dec 2020 02:49:00 PM CST
admin@sonic:~$ show ntp
MGMT_VRF_CONFIG is not present.
synchronised to NTP server (216.239.35.12) at stratum 2
   time correct to within 944 ms
   polling server every 64 s
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
*216.239.35.12   .GOOG.           1 u   36   64    7    5.489   -0.489   0.228