[Working Blog] ONTAP Snapshot Reporting in Python - Part 4 - Getting the Time

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Carrying on from Part 3...

We need to get the time. Here we get the cluster time. It is important to use the cluster time, because your Python client might be in a different timezone. The snapshots use a time naming convention, with the time set by the ONTAP cluster.

(Random thought ... what happens if you have daylight savings clock change ... we'll cross that bridge later ...) (or are ONTAP snapshots names always UTC ... see below)

How to Get ONTAP Cluster Current Time in Python

Below is the input into my Python CLI, showing how to get the day, hour, minute, month and year:

from netapp_ontap import config, HostConnection
from netapp_ontap.resources import Cluster

conn = HostConnection(
  host="CLUSTERNAME",
  username="LOGIN_USER",
  password="LOGIN_PASSWORD",
  verify=False # Set to True if you have valid SSL cert
)

config.CONNECTION = conn

clus = Cluster()
clus.get()

clus.timezone
clus.statistics

clus.statistics.timestamp
clus.statistics.timestamp.day
clus.statistics.timestamp.hour
clus.statistics.timestamp.minute
clus.statistics.timestamp.month
clus.statistics.timestamp.year

The outputs are below:

datetime.datetime(2025, 4, 19, 19, 12, 25, tzinfo=datetime.timezone.utc)
19 #day
19 #hour
12 #minute
4 #month
2025 #year

Now we have time and date from the cluster.

After doing this, it crossed my mind that snapshots might use UTC, and checking, that seems to be so:

Why does ONTAP System Manager always show default snapshot name one or more hour behind cluster time - NetApp Knowledge Base

"By design OSM default snapshot name contains UTC timestamp irrespective of cluster timezone"

Which kinda makes sense. Changing timezone won't change the snapshot names. And no issues with daylight savings changes. So we could just get standard UTC time from Python. How do we do this?

How to Get UTC Time in Python

This is easy:

from datetime import datetime, timezone
datetime.now(timezone.utc)

datetime.now(timezone.utc).day
datetime.now(timezone.utc).hour
datetime.now(timezone.utc).minute
datetime.now(timezone.utc).month
datetime.now(timezone.utc).yer

But it occurred to me that we don't want to use this, we want to get the cluster time as UTC (in case there is time drift between the ONTAP cluster and our Python client.) How do we do this?

ONTAP Cluster Statistics Timestamp is UTC!

On my lab system - which was using UTC - I change the timezone to Australia/Tasmania but the statistics.timestamp still had timezone UTC. Screenshot below:


Now we have the correct time, next step to construct the expected snapshots based on snapshot policy.

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