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Snap automatically refreshes (updates) snaps. It does this by default, and there is no built in option to disable this. A work-around is to create a cron job which adjusts the refresh settings for Snap so that Snap always misses it's window of opportunity.
Steps:
- Configure the Snap refresh timer so that it only refreshes once a month, on the last Friday, between 1:00AM - 2:00 AM. Type "sudo snap set system refresh.timer=fri5,01:00-02:00".
- Create a script which changes Snap's refresh timer settings to 6:00 AM-7:00AM. Create a new file called "snap_timer_forward.sh" in "/scripts", and in it paste:
[quote]
snap set system refresh.timer=fri5,06:00-07:00
[/quote]
- Give the script execution permissions for the root user. Type "chmod u=rwx,g=rx,o=r /scripts/snap_timer_forward.sh".
- Create a script at which changes Snap's refresh timer settings back to 1:00AM-2:00AM. Create a new file called "snap_timer_backward.sh" in "/scripts", and in it paste:
[quote]
snap set system refresh.timer=fri5,01:00-02:00
[/quote]
- Give the script execution permissions for the root user. Type "chmod u=rwx,g=rx,o=r /scripts/snap_timer_backward.sh".
- Create a Cron job which runs snap_timer_forward.sh every day at 12:00AM. Type "sudo -i", "crontab -e", type "1" (for Nano), press "enter", press "down arrow" until you reach the first empty line, paste "00 06,07 * * * /scripts/snap_timer_forward.sh". To save press "control" + "x", type "y", press "enter".
- Create a Cron job which runs snap_timer_backward.sh every day at 3:00AM. Type "sudo -i", "crontab -e", type "1" (for Nano), press "enter", press "down arrow" until you reach the first empty line, paste "00 01,02 * * * /scripts/snap_timer_forward.sh". To save press "control" + "x", type "y", press "enter".
Notes:
- Cron runs daily instead of only on the last Friday of the month, because there is no Cron option for that as far as I know (but I'm not very experienced with Cron).
- To check when Snap last refreshed, and will next refresh type "snap refresh --time".
- To check cron jobs schedules for a particular user (eg: "root") use "sudo crontab -u $user_name -l".
- These steps were tested on Lubuntu 18.04 AMD64. [WARNING THESE STEPS HAVE NOT BEEN FULLY TESTED BECAUSE LUBUNTU 18.04 REFUSES TO ALLOW ME TO CHANGE THE DATE AND TIME OF THE SYSTEM REGARDLESS OF THE METHOD I USE. I CHANGE IT, AND LUBUNTU CHANGES IT BACK A FEW SECONDS LATER.]
- Older versions of Snap are known to be incompatible with these steps, because those versions of Snap lack the required command options.
Authors:James Daniel Marrs Ritchey
License:Ritchey Permissive License v8
Ritchey Permissive License v8:
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