IBM Aspera HST Admin Manual page 217

Creating a Subscription, Snapshots, and Snapshot Differential
1. Create a subscription and decide how to manage its expiration.
# /opt/aspera/bin/aswatchadmin subscribe daemon filepath [options]
By default, subscriptions expire in 24 hours. If your snapshot comparisons will be spaced more than 24
hours apart, either set the expiration time to a duration longer than the time between snapshots (add --
expire_in=seconds to the command) or send a resubscribe command periodically to maintain the
subscription.
For more information on creating subscriptions and resubscribing to them, see
page 215.
In the following example, user aspera subscribes to /projectA/source and the subscription expires in 48 hours:
# /opt/aspera/bin/aswatchadmin subscribe aspera /projectA/source --
expire_in=172800
[aswatchadmin subscribe] Successfully created
subscription {"identifier":"bec581b3-3c34-47d7-
a719-93f26f8272d1","path":"file:////projectA/source","scan_period":
{"sec":9223372036854775807,"usec":999999},"expiration":"2018-03-15T07:39:21Z"}
Record the subscription ID (the value of "identifier" in the output) for use in creating the snapshot. You can also
retrieve the subscription ID later.
2. Create a snapshot.
# /opt/aspera/bin/aswatchadmin create-snapshot daemon subscription_id
If you do not have the subscription ID, run the following command:
# /opt/aspera/bin/aswatchadmin query-subscriptions daemon
In the following example, user aspera creates a snapshot of the directory that is watched by subscription
bec581b3-3c34-47d7-a719-93f26f8272d1:
# /opt/aspera/bin/aswatchadmin create-snapshot aspera bec581b3-3c34-47d7-
a719-93f26f8272d1
[aswatchadmin create-snapshot] Successfully created snapshot 1.
3. After the desired interval, create another snapshot to compare with the previous snapshot.
The snapshot ID is automatically incremented with each create-snapshot command. For example, running
the same command as the previous step outputs a new snapshot:
# /opt/aspera/bin/aswatchadmin create-snapshot aspera bec581b3-3c34-47d7-
a719-93f26f8272d1
[aswatchadmin create-snapshot] Successfully created snapshot 2.
4. Generate the snapshot differential between the most recent snapshot and the snapshot before it.
To create a snapshot differential that outputs a list that can be used by ascp, run the following command:
# /opt/aspera/bin/aswatchadmin snapshot-
differential daemon subscription_id snapshot_id --format=PATH
Where the snapshot ID is the latest snapshot. For example:
# /opt/aspera/bin/aswatchadmin snapshot-differential aspera
bec581b3-3c34-47d7-a719-93f26f8272d1 2
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Managing Watch Subscriptions on