Silly question time: When the clamav-freshclam service is running, how often is clamav checking for updates? Or do I have to manually run freshclam via a cronjob?
Unless you setup a cronjob it will not check for updates.
The purpose of a cronjob is to automate the process. You can decide to run it in the following:
I recommend cron.daily and set it up via a shell script.
This will now run with all your other cron.daily jobs
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